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Enabling EPP SLI memory does...almost nothing?

V

Venek

Weaksauce
Joined
Jun 1, 2009
Messages
65
After flashing a BIOS update and loading defaults, I figured I'd give the SLI memory feature a chance before going back to conventional overclocking (which I haven't yet).

Supposedly enabling EPP in the BIOS is supposed to overclock my RAM to its maximum safest potential without having to do anything else. I set it to the max value and...I didn't really see much of a difference in the timings in CPU-Z.

Also, why can't I overclock my CPU while having SLI memory enabled? I'm thinking I'll just end up going back to conventional overclocking, except I never oc'ed RAM before and not quite sure what safe numbers I can use.

Thanks
 
ok if the ram has an EPP setting.. say for example ddr2 1066 ram by default loads at ddr2 800 5-5-5-18.. but the ram supports ddr2 1066 5-5-5-15 using the EPP setting.. when you enable EPP mode on your motherboard it will just change the settings to ddr2 1066 5-5-5-15 timing.. some ram support the EPP option.. some dont and you have to manually adjust it in the bios..
 
Supposedly enabling EPP in the BIOS is supposed to overclock my RAM to its maximum safest potential without having to do anything else.
Click to expand...

I do not think that is quite exactly correct in the way you are thinking about it. Yes, it should set the main timings fairly agressively, but it is the second part of your statement that is a bit off.

The first thing to realize is that the EPP profiles are set by the manuf and typically they are higher performance than the default JDEC specs that are used if the memory settings are placed on auto but the EPP settings do not have to be super agressive it just depends on what the manuf thinks they can get the memory to do in a higher performace mode on most boards. No way they can anticipate every OCing situation. Also typically the profiles are at particular FSB points. So profiles are mainly just a rough shot at better performance settings. Well that is not entirely fair. Some companies do a better job at an effective EPP than others.

What you do not see is the many sub-timings that are adjusted for better performance. Here is a tool that will let you see all the things that are/can be tweaked in the SPD chip.

http://www.techpowerup.com/spdtool/

The above program can be used to change values in the SPD chip, make sure you just Read values, do not Write unless you know exactly what you are doing and even then I dont recommend changing the SPD values.

In short the EPP is just a step in the right direction and there is no way the EPP can account for every OC situation or even the normal differences found in each and every board.
 
Thanks to the both of you, your info helped me out immensely.

Sirmonkey, you were right in that it did change the frequency setting of the RAM from 800 to 1066. That's actually what I want it to do, except I also wanted to have a faster CPU (from 2.4 to 3.4).

BillParrish, you explained it clearly what exactly the story is about with EPP modules. It looks like I only received a small performance gain, enough to be noticeable, but not enough to make a difference.

Looks like I'll have to oc stuff manually. Could either of you point me in the right direction in terms of FSB to RAM frequency ratio? I just learned about this recently and realized I could get far more efficient performance at an optimal ratio.
 
Well in general this is what you want to do to start.

Use a 1:1 ratio for starters on memory while you see how high you can take the FSB and OC the CPU. This will underclock the memory well below its rated speed but it takes it out of the mix so you can find a good stable FSB to run your CPU at. Keep in mind that in 95% of the software we typically use CPU MHz are much much more powerful than memory MHz. So the idea is to get your cpu where you want it then go back and adjust memory mulitpliers to get some memory speed close to its rated speed or a little faster. Even if you have to choose a memory mulitplier that still results in your memory being slightly underclocked you are still better off.

Once you find a memory mulitplier that is close you can go two ways. One would be if the memory is underclocked is to see if you can tighten the timings a bit to reduce latencys. The second thing you could try is to loosen the timings and see if you can get the memory to run at the next mulitplier/speed. Keep in mind either way you will not see a big difference in performance as mentioned its more about the CPU.

So the cpu runs at the cpu mulitplier x the FSB.

The memory runs at 2 x the FSB x the ratio (well different bios list it different ways but the idea is the same. Gigabyte just gives a memory mulitplier and you can just do FSB x memory mulitplier to determine the ram speed. Others will have something like 5:4 or 5/4 so with a 400MHz FSB the memory speed would be 2 x 400 x 5/4 = 1000Mhz.

As mentioned different manuf label things different ways, I think you have an Nvidia chipset board since you have the SLI option in the bios. There should be an option to "unlink" cpu speed from memory speed and that would allow you to set the FSB to a wider range of values.

If you tell us your cpu model number and board Manuf and model number and same for memory (newegg links are great ) lots of people here could help you with settings, someone has already been where you are going and should have some good examples of starting points for bios settting.s
 
I've actually already oc'ed my CPU before, so I know how to do that much. In fact, now that I think about it, enabling my EPP RAM actually decreased my CPU's multiplier down to 6 but increased the FSB to keep it at its rated 2.4ghz while increasing my RAM's frequency to 1066. So I guess the EPP profile DID work as designed.

I'm not happy with just 2.4, though, I'd like to crank it up to 3.4 if possible or at least 3.2, but not quite sure how to overclock (or underclock?) the RAM to keep the speed proportional to each other. I had no problem oc'ing the CPU, and I have a good heatsink/fan to take care of the heat.

Here's my specs:

Mobo: EVGA nForce 680i SLI - I believe the model is 122-CK-NF68-AR (default multiplier in BIOS is 9): http://www.newegg.com/Product/Product.aspx?Item=N82E16813188009

CPU: Intel's Conroe E6600 - 2.4 ghz FSB rated at 1066: http://www.newegg.com/product/product.aspx?Item=N82E16819115003

RAM: 2 gb Corsair DDR2-1066 Dominator (PC2-8500) - model is TWIN2X2048-8500C5D: http://www.newegg.com/Product/Product.aspx?Item=N82E16820145043&Tpk=dominator

I'm going to have reread your post a few times BillParrish to get a handle on the math and make sense of it, I know I'll get there.

Thanks again!

*EDIT* By the way, I'm thinking about upgrading my CPU to the Wolfdale E8400: http://www.newegg.com/Product/Product.aspx?Item=N82E16819115037

It's at a very decent price and I can't but wonder if I'll get a better performance boost as a result. What do you think?
 
Venek said:
I'm not happy with just 2.4, though, I'd like to crank it up to 3.4 if possible or at least 3.2, but not quite sure how to overclock (or underclock?) the RAM to keep the speed proportional to each other. I had no problem oc'ing the CPU, and I have a good heatsink/fan to take care of the heat.
Click to expand...
With Core 2 systems, CPU speed provides much more of a performance advantage than faster memory does. In general, when overclocking the CPU you want to keep your RAM as low as possible while finding a maximum CPU overclock, and then you try raising your RAM as much as you can while still maintaining the same CPU overclock stably. So if you want to overclock, my recommendation would be to actually ditch the EPP for now and work on getting to your highest CPU speed, and then once you have that, start playing around with your RAM again. You may find that you can't actually run the RAM at its EPP settings when your CPU is overclocked to its maximum, so you might have to decide between keeping EPP or your CPU overclock.

To be honest though, I'm not really sure how EPP works altogether when paired with CPU overclocking, so you may have to forgo it anyway. So just try playing around with different things to see what settings affect what, and then try and figure out how you want everything set up.
 
as far as intel systems.. the only thing i can see that when enabling the EPP mode is that it increased the FSB to raise the memory.. but then that would just be stupid since the motherboard already supports 1066 through the ram multiplier..

if your going to overclocking.. first things first is turn off the EPP crap.. since you wont be able to overclock with that on.. and then have fun overclocking.. everytime you hit 1066 on your ram due to increasing the FSB.. you need to drop the multiplier on the ram down one.. then increase the FSB some more..

like zero said.. you want to set your ram speed as low as possible.. eg.. 1:1 timing with the FSB.. so if your fsb is at 400 your ram is at 400(ddr2 800)..

and yes the e8400 will make your e6600 look like a p4 performance wise..
 
sirmonkey1985 said:
and yes the e8400 will make your e6600 look like a p4 performance wise..
Click to expand...
Not by a long shot. An E8400 is at most 10-15% faster clock-for-clock compared to an E6600. The only real advantage is overclocking, but even that isn't really enough of an incentive to go with a faster dual-core like an E8400 rather than getting a quad-core like a Q8400 or Q9400 which can be found for fairly cheap these days.
 
Zero82z said:
Not by a long shot. An E8400 is at most 10-15% faster clock-for-clock compared to an E6600. The only real advantage is overclocking, but even that isn't really enough of an incentive to go with a faster dual-core like an E8400 rather than getting a quad-core like a Q8400 or Q9400 which can be found for fairly cheap these days.
Click to expand...


yeah i agree with the quad.. but in the end it all depends on what he does.. if all he does is play games.. an e8400 will be just as fast as the quads..

but id rather have the overclocking headroom of the e8400 then the e6600 in my opinion.. but thats just me since nothing i own sits at stock speeds except for the first boot up after install..
 
sirmonkey1985 said:
but id rather have the overclocking headroom of the e8400 then the e6600 in my opinion.. but thats just me since nothing i own sits at stock speeds except for the first boot up after install..
Click to expand...
The overclocking headroom is nice, but it's certainly not worth the cost of an E8400 just for that purpose compared to sticking with the E6600.
 
I think what I'll do is overclock what I have now in order to determine whether or not I should upgrade my CPU. Sirmonkey's correct in that I really only use my computer for gaming in addition to the usual web surfing and occasional Photoshopping or working in Illustrator. I don't do any 3D modeling or anything like that, otherwise I could see justifying the cost for a new quad.

So when you're talking about dialing down the multiplier for the RAM while increasing the FSB, are you talking about the same one for the CPU? (which sits at 9x) Does this mean, then, that in overclocking my system that I keep the FSB and RAM linked as opposed to unlinked so I can determine the ratio and what multiplier to use?

What I'm getting from this is that I keep it linked, run up the FSB to where I want it to be (probably 1512 to get a 3.4) and then knock down the multiplier until the RAM reads 1066. Is this correct? Is there another multiplier I'm missing somewhere?

Thanks again all!
 
Venek said:
So when you're talking about dialing down the multiplier for the RAM while increasing the FSB, are you talking about the same one for the CPU? (which sits at 9x)
Click to expand...
No, just the memory multiplier. It's best to keep your CPU multiplier as high as possible to avoid running into FSB bottlenecks that limit your overclock.
Venek said:
Does this mean, then, that in overclocking my system that I keep the FSB and RAM linked as opposed to unlinked so I can determine the ratio and what multiplier to use?
Click to expand...
I didn't realize you had a 680i board at first. What I would suggest is that you try both unlinked mode with your memory running at a slow speed, and then try it linked also with your RAM as low as possible, and see which mode lets you reach a higher CPU FSB. Then just use whatever settings let you get your CPU as high as possible, and then start working on your memory.
 
So, the memory multiplier is the one that reads MEM (DDR), MHz followed by a number, correct? I guess I thought it would be a single digit like the CPU multiplier, I got mixed up.

Anyway, I tinkered around in BIOS tonight, seeing what options does what but not actually saving anything for fear of a mushroom cloud rising above my desk.

I've gone up as high as 3.4 on my CPU before and it ran stable (at default voltage settings, no less!). So I know I can push my CPU probably to 3.6 with a bump or two in my voltage (that would be the CPU core, right? NOT CPU FSB? Or maybe both? I clearly have learning to do about voltage settings).

The RAM I have is rated to go 1066 mhz, does this mean I want it go that high for better performance or use that number as a divider to go slower but allow faster CPU speeds?

The last question I have is which of the four ratio options is best? I have Auto, 1:1:, 5:4, 3:2, and Sync Mode, and they all yield different results depending on the number I plug in the FSB. The best number I've seen so far (but did not actually use) is a FSB of 1600 (for 3.6 ghz) and getting 1066 for the RAM in I think it was 3:2 ratio.

Is it OK to go ahead and jump my FSB to 1424 since that was the number I used for a good long while and ran stable? I was thinking of at least going to 3.0 and let the RAM go where it may in one of those ratio modes,.not going over 1066, obviously. (I had to load defaults after flashing a BIOS update)

Am I getting somewhere here or am I going to accidentally kill my computer?
 
Venek said:
So, the memory multiplier is the one that reads MEM (DDR), MHz followed by a number, correct? I guess I thought it would be a single digit like the CPU multiplier, I got mixed up.
Click to expand...
The memory multiplier is the setting that determines your memory speed based on the FSB. It's not a straight-up number like the CPU multiplier, and it's often represented either by a ratio (FSB:RAM) or by listing the final frequency of the memory (it'll just say something like DDR2-800).
Venek said:
I've gone up as high as 3.4 on my CPU before and it ran stable (at default voltage settings, no less!). So I know I can push my CPU probably to 3.6 with a bump or two in my voltage (that would be the CPU core, right? NOT CPU FSB? Or maybe both? I clearly have learning to do about voltage settings).
Click to expand...
CPU FSB and CPU core voltages are two different things.
Venek said:
The RAM I have is rated to go 1066 mhz, does this mean I want it go that high for better performance or use that number as a divider to go slower but allow faster CPU speeds?
Click to expand...
It just means that your RAM is guaranteed to run stably at 1066MHz. However, that doesn't mean you should run it at that speed, because like I said earlier, the CPU speed is much more important performance-wise than the RAM speed, so you should aim to get your memory as high as possible without having to back down on your CPU overclock. You may not be able to both max out your CPU and run your RAM at 1066MHz stably, so in that case, I would recommend that you back down your memory speed and not your CPU speed.
Venek said:
The last question I have is which of the four ratio options is best? I have Auto, 1:1:, 5:4, 3:2, and Sync Mode, and they all yield different results depending on the number I plug in the FSB. The best number I've seen so far (but did not actually use) is a FSB of 1600 (for 3.6 ghz) and getting 1066 for the RAM in I think it was 3:2 ratio.
Click to expand...
The "best" ratio is just the one that lets you run your FSB and RAM at whatever their maximum stable speeds are. Once you have your CPU overclock all set, try and use the RAM multipliers to get your memory as high as possible while keeping it stable.
Venek said:
Is it OK to go ahead and jump my FSB to 1424 since that was the number I used for a good long while and ran stable? I was thinking of at least going to 3.0 and let the RAM go where it may in one of those ratio modes,.not going over 1066, obviously. (I had to load defaults after flashing a BIOS update)
Click to expand...
There's no problem with jumping straight to that FSB speed. You'll just have to play around and try a few different things until you find the maximum settings that you're comfortable with.
Venek said:
Am I getting somewhere here or am I going to accidentally kill my computer?
Click to expand...
If your computer dies, it'll probably be because of the motherboard and not because of anything you do ;). We're staying firmly in the safe zone of overclocking here.
 
Zero82z said:
The memory multiplier is the setting that determines your memory speed based on the FSB. It's not a straight-up number like the CPU multiplier, and it's often represented either by a ratio (FSB:RAM) or by listing the final frequency of the memory (it'll just say something like DDR2-800).

CPU FSB and CPU core voltages are two different things.

It just means that your RAM is guaranteed to run stably at 1066MHz. However, that doesn't mean you should run it at that speed, because like I said earlier, the CPU speed is much more important performance-wise than the RAM speed, so you should aim to get your memory as high as possible without having to back down on your CPU overclock. You may not be able to both max out your CPU and run your RAM at 1066MHz stably, so in that case, I would recommend that you back down your memory speed and not your CPU speed.

The "best" ratio is just the one that lets you run your FSB and RAM at whatever their maximum stable speeds are. Once you have your CPU overclock all set, try and use the RAM multipliers to get your memory as high as possible while keeping it stable.

There's no problem with jumping straight to that FSB speed. You'll just have to play around and try a few different things until you find the maximum settings that you're comfortable with.

If your computer dies, it'll probably be because of the motherboard and not because of anything you do ;). We're staying firmly in the safe zone of overclocking here.
Click to expand...

Actually, according to my BIOS screen, there's a voltage setting for both the CPU and the CPU FSB (it reads that way). It doesn't matter anyway, I'm not going to touch the voltage settings if I can help it.

Now I'm beginning to finally understand the whole deal with FSB - Memory ratio and what the ideal setting is. Right now I'm running at 3.0 ghz (1333 mhz) while linked to the RAM in Sync Mode and that resulted in tbe BIOS automatically setting the RAM at 333 mhz, clearly a 1:1 ratio. So even though the RAM is technically moving slower, I was pleasantly surprised to see such a HUGE performance boost in my computer! Everything's much faster now and now I wonder why I didn't do that the first time I oc'ed the CPU!

CPU temp is at a very respectable 52C (thank you Arctic Cooling Freezer 7 Pro!). I'm going to see if I can't maintain a 1:1 ratio in Sync Mode after I bump up the CPU to 3.2 and maybe 3.4. That's my stopping point right there. If I can still boot up and do normal tasks in 3.4 and whatever RAM is set at, I'll run Prime95 for a night and hope I wake up to humming computer. Er, maybe I should do that during the day and do a LOTR marathon or something.

In any case, thanks to you all, I'm gaining an understanding (and appreciation) of the relationship between the CPU and RAM.
 
Venek said:
I've actually already oc'ed my CPU before, so I know how to do that much. In fact, now that I think about it, enabling my EPP RAM actually decreased my CPU's multiplier down to 6 but increased the FSB to keep it at its rated 2.4ghz while increasing my RAM's frequency to 1066. So I guess the EPP profile DID work as designed.

I'm not happy with just 2.4, though, I'd like to crank it up to 3.4 if possible or at least 3.2, but not quite sure how to overclock (or underclock?) the RAM to keep the speed proportional to each other. I had no problem oc'ing the CPU, and I have a good heatsink/fan to take care of the heat.

Here's my specs:

Mobo: EVGA nForce 680i SLI - I believe the model is 122-CK-NF68-AR (default multiplier in BIOS is 9): http://www.newegg.com/Product/Product.aspx?Item=N82E16813188009

CPU: Intel's Conroe E6600 - 2.4 ghz FSB rated at 1066: http://www.newegg.com/product/product.aspx?Item=N82E16819115003

RAM: 2 gb Corsair DDR2-1066 Dominator (PC2-8500) - model is TWIN2X2048-8500C5D: http://www.newegg.com/Product/Product.aspx?Item=N82E16820145043&Tpk=dominator

I'm going to have reread your post a few times BillParrish to get a handle on the math and make sense of it, I know I'll get there.

Thanks again!

*EDIT* By the way, I'm thinking about upgrading my CPU to the Wolfdale E8400: http://www.newegg.com/Product/Product.aspx?Item=N82E16819115037

It's at a very decent price and I can't but wonder if I'll get a better performance boost as a result. What do you think?
Click to expand...

The 680i SLI is actually quite good at making use of the EPP feature on memory modules. I've used it with both Corsair RAM and OCZ RAM with nothing but success. EPP is designed to allow for automatic configuration of your RAM on a board supporitng the feature. It clocks the RAM and sets the timings for what the RAM is rated for instead of JEDEC specifications. In other words EPP simply takes the need to configure RAM rated for speeds greater than JEDEC specifications manually. The feature also worked well on 780i SLI reference boards. The 790i Ultra SLI and 790i SLI FTW didn't work so well though. Intel's XMP technology is essentially the same thing but I've yet to see it work properly.

As for the E8400, I wouldn't bother. Generally speaking the EVGA 680i SLI won't overclock the 45nm dual core CPUs as well as it overclocks the 65nm CPUs. Honestly going from a dual core 65nm CPU to a dual core 45nm CPU doesn't make much sense to me. The improvement between the two doesn't really justifiy the cost. I own both an E6600 and the E8400 and really there isn't much difference between the two of them in general tasks. Yes the E8400 will overclock much better but not on your board. The E6600 should be good for 3.4GHz at least on that board if not more. I got mine to 3.6GHz to give you an idea of what it can do.

I'd generally suggest going to a quad core if you want a real upgrade (as going to a slightly faster dual core doesn't make too much sense to me), but given the board you are using I can't really recommend one. The 122CK-NF68-AR doesn't support 45nm Quad Core CPUs and it can't overclock the 65nm dual core CPUs very well at all. There was a hardware change that had to be made for the EVGA 680i SLI to overclock the Core 2 Quad's to any significant degree. New part numbers were issued to denote the change. 122CK-NF68-A1 and 122CK-NF68-T1. There was also a 122CK-NF69-A1 which was the EVGA Black Pearl. It was equipped with Innovotek waterblocks covering the north bridge, south bridge, and MOSFETs.
 
Venek said:
Actually, according to my BIOS screen, there's a voltage setting for both the CPU and the CPU FSB (it reads that way). It doesn't matter anyway, I'm not going to touch the voltage settings if I can help it.
Click to expand...
Yes, like I said, the CPU voltage and the CPU FSB voltage are two different things ;).
 
BillParrish said:
Here is an overclocking guide put out by Nvidia that may help you get started.

http://www.nvidia.com/docs/CP/45121/nforce_680i_sli_overclocking.pdf

Do not be afraid to give the CPU some some voltage , it is where you get most of the OCing from. Up to 1.375V is very safe.
Click to expand...

Thanks, but I've already had that guide for months and used it when I started OC'ing months ago. It's an excellent guide.

My only question when it comes to voltage settings is that there's several listed and I'm not sure which one to up the volts. I'm assuming it's the CPU Core (would that be Vcore?) but don't want to do anything until I know for sure. MANY thanks for the that 1.375 number, that's extremely handy to know.
 
Venek said:
My only question when it comes to voltage settings is that there's several listed and I'm not sure which one to up the volts. I'm assuming it's the CPU Core (would that be Vcore?) but don't want to do anything until I know for sure. MANY thanks for the that 1.375 number, that's extremely handy to know.
Click to expand...
There are several voltages that you can tweak to help you reach higher speeds. The CPU core voltage is generally the most important one though.
 
Zero82z said:
There are several voltages that you can tweak to help you reach higher speeds. The CPU core voltage is generally the most important one though.
Click to expand...

Eeeyyyiiiiiiiiii! I just went into my BIOS and discovered that it had been setting the voltages automatically! This freaks me out a little bit because if I had gone higher, I might have run the risk of cooking my CPU and board. Fortunately, it was only sitting at 1.4, so that's not TOO high for comfort. I'm currently running at 3.2 and my temp right now is reading 52 (Speedfan), so I guess I'm pretty satisfied with that.

Now, regarding RAM, in my CPU-Z, I have 3 timing tables, 2 JEDECs and an EPP. Right now, the voltage for it is set around 1.8, but the EPP table shows that I can put in 2.1 to get a frequency of 533, timings of 5-5-5-15 and a command rate of 2T, whatever the hell that is (someone please enlighten me). So, I'm guessing if I plug in 2.1 volts for my RAM, I can increase my RAM to either 533 or 1066 proportionally to my CPU speed? Or maybe that's what the Expert mode is for in enabling SLI memory?
 
Venek said:
Now, regarding RAM, in my CPU-Z, I have 3 timing tables, 2 JEDECs and an EPP. Right now, the voltage for it is set around 1.8, but the EPP table shows that I can put in 2.1 to get a frequency of 533, timings of 5-5-5-15 and a command rate of 2T, whatever the hell that is (someone please enlighten me). So, I'm guessing if I plug in 2.1 volts for my RAM, I can increase my RAM to either 533 or 1066 proportionally to my CPU speed? Or maybe that's what the Expert mode is for in enabling SLI memory?
Click to expand...
You may be able to set your RAM settings to the EPP timings, but like I explained above, those settings may not be stable with your CPU overclocked as well. I'm not very familiar with EPP in general, but I would imagine that there is a specific setting in your BIOS to enable it, since there are also many subtimings that aren't listed in CPU-Z but are still changed when using the EPP profile.
 
Zero82z said:
You may be able to set your RAM settings to the EPP timings, but like I explained above, those settings may not be stable with your CPU overclocked as well. I'm not very familiar with EPP in general, but I would imagine that there is a specific setting in your BIOS to enable it, since there are also many subtimings that aren't listed in CPU-Z but are still changed when using the EPP profile.
Click to expand...

On the 680i SLI that doesn't matter since the RAM settings and CPU/FSB settings can be adjusted independently of one another. Case in point, on my 680i SLI boards I used OCZ Flex XLC PC2-9200 DDR2 1150MHz RAM which supported EPP (later referred to as SLI-Ready memory.) When EPP was enabled the RAM automatically ran at 1143MHz using its rated timings of 5,5,5,18. Voltage settings were the only thing that was a little off. I believe the EPP value was 2.3v and the RAM usually ran at 2.1v without issues. OCZ did warranty the RAM for up to 2.3v as I recall. On that same system I ran my Core 2 Quad Q6600 at 3.6GHz - 3.8GHz on water. (Depending on the board I had. I went through 12 of the reference boards and not all of them overclocked as well as others.) This required an FSB of 422.2MHz. The memory bus would have been 571MHz. It was a neat design. Too bad the 790i Ultra and EPP 2.0 didn't work as well.

Being able to run your CPU FSB and memory bus clocks independently was one of the coolest features of the 680i SLI chipset based boards. Its a shame NVIDIA really screwed up the design in other areas.
 
Last edited:
Dan_D said:
That depends. On the 680i SLI it doesn't matter so much. Since the RAM settings and CPU/FSB settings can be adjusted independantly, this is not always so. That part of the 680i SLI reference design was one of its good points.
Click to expand...
Very true. I have however read of cases where running the RAM in linked mode would allow for higher CPU overclocks than unlinked, and vice versa. As always, there's no way to know what will be stable and what won't be without actually testing it.
 
Zero82z said:
Very true. I have however read of cases where running the RAM in linked mode would allow for higher CPU overclocks than unlinked, and vice versa. As always, there's no way to know what will be stable and what won't be without actually testing it.
Click to expand...

True, but I've had a lot of these boards (12 reference, 1 non-reference to be precise.) On my ASUS Striker Extreme the EPP function didn't work at all with the above mentioned OCZ RAM. It did work fine with my 900MHz Patriot modules. The reason? The Striker Extreme was poorly designed in that it couldn't usually go beyond 900MHz DDR2 without issues. It was a quirk of the design. All of the non-DOA reference boards I had, (over half a dozen) all worked with the EPP settings and timings for the RAM I mentioned above. So that's a pretty good sampling of them. They worked equally well with Corsair Dominator PC2 8500MHz modules.
 
Well, I just went into BIOS, enabled my SLI memory but went into expert mode so I could still overclock the FSB and RAM independently. I left my CPU at 3.2 for now, though, but I did change all of the settings for my RAM to run at 5-5-5-15, 2T and at 1066 while remembering to up my volts to 2.1 for it (all settings per EPP ratings as published by Corsair). Works beautifully so far! The ratio may be 2:3 as it reads in CPU-Z, but I definitely noticed my computer kicking it up a couple of notches by doing some intensive 3D rendering in Illustrator and some Photoshop filters/effects.

OK, so EPP memory do have a valid claim, but I think I'm starting to realize that I could've done exactly what I just did without forking over an extra $10 using conventional overclocking on RAM with the same settings but without the label. That's not to say that EPP memory doesn't have its merits, though, I think they can be quite handy for someone brand-new to overclocking as they are gentle, for lack of a better word.
 
Venek said:
Well, I just went into BIOS, enabled my SLI memory but went into expert mode so I could still overclock the FSB and RAM independently. I left my CPU at 3.2 for now, though, but I did change all of the settings for my RAM to run at 5-5-5-15, 2T and at 1066 while remembering to up my volts to 2.1 for it (all settings per EPP ratings as published by Corsair). Works beautifully so far! The ratio may be 2:3 as it reads in CPU-Z, but I definitely noticed my computer kicking it up a couple of notches by doing some intensive 3D rendering in Illustrator and some Photoshop filters/effects.

OK, so EPP memory do have a valid claim, but I think I'm starting to realize that I could've done exactly what I just did without forking over an extra $10 using conventional overclocking on RAM with the same settings but without the label. That's not to say that EPP memory doesn't have its merits, though, I think they can be quite handy for someone brand-new to overclocking as they are gentle, for lack of a better word.
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On a board that uses the feature correctly, there would be value in EPP for OEM systems. It would or could make things easier for system builders.
 
So much for running stable at 3.2 on 1.4, my computer rebooted itself last night. After rereading NVIDIA's overclocking guide, I learned that it's safe to go up to about 1.57 or 1.58 volts for the CPU. So, I'm thinking I'll switch back to automatic voltage setting for the CPU only and let the BIOS determine the optimal volts.

Quick question regarding RAM volts. I currently have it set at 2.1 as per the specs, but will it hurt anything if I kick it up to 2.2? I'm wondering if this might be the reason my 'puter rebooted and not the CPU.

I'm going to do a final overclock tonight to 3.3 to hit the sweet spot of a 1:1 ratio with 533mhz RAM frequency. I'll probably run Orthos overnight to finalize things. Still can't play games yet, though, not until Pantone sends me my Huey replacement! (I got a defective one, figures!)
 
Venek said:
After rereading NVIDIA's overclocking guide, I learned that it's safe to go up to about 1.57 or 1.58 volts for the CPU.
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No, it most certainly is not. The maximum safe voltage for your CPU is 1.5V. And I wouldn't recommend letting the BIOS set the voltage automatically. Just raise it yourself bit by bit and see if you can get it stable. If not, you'll have to work on tweaking other settings.
Venek said:
Quick question regarding RAM volts. I currently have it set at 2.1 as per the specs, but will it hurt anything if I kick it up to 2.2?
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You might be able to, but I personally wouldn't be comfortable with it. After the Crucial Ballistix debacle, I'm very wary of taking RAM past its rated voltage.
Venek said:
I'm wondering if this might be the reason my 'puter rebooted and not the CPU.
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I don't understand what you mean by that.
 
Zero82z said:
No, it most certainly is not. The maximum safe voltage for your CPU is 1.5V. And I wouldn't recommend letting the BIOS set the voltage automatically. Just raise it yourself bit by bit and see if you can get it stable. If not, you'll have to work on tweaking other settings.
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Well the maximum safe voltage probably differes slightly from CPU to CPU. However, 1.5v is generally as high as you want to go with a Core 2. On a 680i SLI board absolutely, for no reason, ever, ever, leave your CPU voltage (or most other voltage settings for that matter) on "AUTO" as it will seriously tax the boards voltage hardware. (This statement only applies to NVIDIA chipset based reference boards such as the EVGA 680i SLI. Part numbers 122CK-NF68-A1, 122CK-NF68-AR, 122CK-NF68-TR, 122CK-NF68-T1, 122CK-NF69-A1, etc. These boards were also sold by XFX and BFG Technologies. I am unfamiliar with their part numbering scheme as all my boards were EVGA branded. Not only can this potentially destroy the board but it can hurt your CPU. The 680i SLI boards, while quite capable of easy overclocking on automatic settings tend to use far too much voltage in order to make the system stable. While this works in the short term, in the long run these boards will burn themselves up doing this. Watch your voltage monitor and you'll see what I'm talking about. The board will push voltages well beyond the safe limits of your hardware. EPP RAM for example will often end up at 2.3v when the EPP tables only call for 2.1v. CPU voltage on automatic settings will often end up well north of 1.5v. These things have a hard enough time keeping thier voltages in check with what you've manually set them too, don't trust them on "AUTO." I can promise you that your results however good, will be probably be short lived. Also, manually controlling these settings and keeping them as low as possible will help your temperatures and ease the stress on board components.
 
Dan_D said:
Well the maximum safe voltage probably differes slightly from CPU to CPU. However, 1.5v is generally as high as you want to go with a Core 2.
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Well, the maximum functional voltage based on the CPU specifications is 1.5V. It's true that some chips may be able to go higher without incurring damage, but the only way (for the average person) to determine the true voltage limit of a CPU is by actually raising the voltage until the chip starts to degrade from overvolting, and by that point the information is fairly useless anyway. So that's why I state a hard limit of 1.5V for people who expect some amount of longevity from their CPU's lifespan.
 
Zero82z said:
Well, the maximum functional voltage based on the CPU specifications is 1.5V. It's true that some chips may be able to go higher without incurring damage, but the only way (for the average person) to determine the true voltage limit of a CPU is by actually raising the voltage until it starts to degrade from overvolting, and by that point the information is fairly useless anyway. So that's why I state a hard limit of 1.5V for people who expect some amount of longevity from their CPU's lifespan.
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Right. I was speaking more academically than anything else.
 
Just for the record, I'm currently running 3.4ghz on only 1.35 but Vcore shows only 1.32! Either I got really lucky with my set-up or the reading's off, and I'm betting it's the former. Now I see why so many people raved about the EVGA 680i and the E6600! Forget upgrading, I'm sticking with this sucker! I might even push my luck and see if I can't go up to 3.6!
 
Venek said:
Just for the record, I'm currently running 3.4ghz on only 1.35 but Vcore shows only 1.32! Either I got really lucky with my set-up or the reading's off, and I'm betting it's the former. Now I see why so many people raved about the EVGA 680i and the E6600! Forget upgrading, I'm sticking with this sucker! I might even push my luck and see if I can't go up to 3.6!
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The software always reports a slightly inaccurate reading. This is true of all motherboards. The ASUS Rampage II Extreme was actually the most accurate in terms of voltage reporting but it actually has the probe wires to allow you to accurately measure the values with a volt-meter. Something you can't easily do with most boards. In any case, the readings are always off like I said. The actual voltage dropping below the set voltage is what we call vdroop.
 
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