E6300 Overclocking.

[DasOmen]

So I'm from the good ole' days of unlocked 2500+ Barton overclocking pushing it to the limits and have gone back and forth between wanting to OC my C2D in my new system but for a while decided against it as I didn't really need the power at the time. I mainly run Visual Studio 2008 pro, Adobe CS, and Winamp with the occasional COD games. However I have decided I want to OC it and squeeze some extra performance out of it. Heres the specs.

E6300 Conroe
ASUS P5N-E32 SLI
2gig (2x1gb) Geil DDR2 800 @ 5-5-5-15
Cooler Master Silent HSF
Cooler Master 650watt PSU

Once not too long ago I OC'ed it by setting the FSB to 1600 and putting it in synced mode (What exactly is the "state" of synced mode anyway?) according to the recomendations of some people. It booted and CPUZ registered 2.8ghz at 1600FSB and the memory at 400mhz as it should be. It ran stably in OrthosII for almost 4 hours but after gaming for a couple hours it would freeze or crash (hard restart) so I downclocked it back to stock.


Today thinking it's because I never changed the Vcore (I left it on auto back then) I put it back on the OCed settings with Vcore still auto and rebooted and CPUZ showed the Vcore to be 1.58......Thats insanely high so I went back to the Bios and set to stock speed but manually set the Vcore to 1.35 (It always showed ~1.42 on default settings and auto voltage) abd checked CPUZ. Sure enough with a manually set 1.35 Vcore CPUZ was registering a ~1.42 Vcore which makes me think I can't trust it and that the 1.58 I saw earlier isn't correct?????

My other problem is this: I know in a real world situation 1:1 ratio is better then 3:2 due to throughput and bottle-necking issues when you take them out of balance. However when I set it to Linked with a ratio of 1 to 1 and a Bus of 800 (thus Mem mhz 800) it wont boot. This doesn't make sense, the Bus is at 800 (processor is built for 1066) and the mem is 800 which is it's rated speed and it wont even make it to post. I instead tried 3:2 with a modest 1200 FSB giving a 300 bus speed and 400 mem speed and it boots fine to 2.1ghz. This is a mild overclock over the 266.7 Bus, 1066 FSB, and 400 mem but I would really like to have it in 1:1 and reach ~2.5+. Any advice?


Edit: Update- I put it back in Synced mode, 1600 FSB (Bus speed showing as 400) and it's at 2.8ghz. I did however set the Vcore to 1.4 manually and it booted and ran fine in CODWaW just now . So it boots fine at 1.4 where as with auto Vcore it would show up hitting 1.6.

Also, what is the diff between Synced and 1:1 because right now it's on synced but showing up as 1:1 in CPUZ.

 

[BillParrish]

Synced is 1:1 let me try and explain.

OK when Intel says a CPU is x buss they are really saying that inside the CPU they multiply the FSB speed by four. (your mother board is doing the same when reporting the FSB). So your 6300 which is a 1066 Intel internal speed is looking for at stock a "raw" FSB of 266MHz . A 1600MHz buss speed as reported by the motherboard is 1600/4 = 400FSB.

Here is the key point, on an Intel system the designers (Intel) standardized on the memory running at 2 x the CPU FSB. This is called synced because when the memory is running at an clock speed that is 2 x the clock provided to the CPU the MCH/Northbridge does not have to introduce wait states or buffering to manage the data flow. Everything is synced up, think of it as everyone in the row boat rowing to the same cadence exactly as you are thinking.

Your problem with the 800MHz (200 FSB) boot issue is that strange as it sounds the CPU does not like the way below stock FSB, normally to go into low power mode Intel drops the CPU multiplier from the max of 7 for your CPU to 6 to slow it down.

The setting of your edited update are ideal and I would work at stabilizing it there, A fan on the MCH/Northbridge heatsink would help. You can likely get a few more MHz out of it but your memory will start to limit you as you cannot go less than 1:. Somewhere around 415-425 MHz FSB (memory running 830 -850MHz) your memory will crap out and you will need to relax your memory timings.

Make sure it is stable where you have it now, Then start slowly raising the FSB a couple of MHz at a time (I would boot into a memtest CD so you don't trash your windows install with a freeze) and see where memtest86+ starts showing errors, Then try 5 5 5 18 and see if it will run without memtest errors. It will be a difficult to get much higher unless you go to 6 x x x timings and you likely don't want to do that. Actually if you can get to 3.2 GHz (FSB at around 457 MHz - memory very OCed at 914MHz ) you will really see what that CPU can do. However this is a fairly high FSB and your cooling has to be up to snuff and your memory will likely be what holds you back. Check with the memory manuf as to what the max memory voltage is. stock is 1.8V many will allow up to 2.1V and more voltage will help it OC. Test memory temp with your finger, fairly warm is fine, hot is not. My rule of "finger' is that if I cannot keep my finger on it for a slow count of ten it is too hot.

1.45 Vcore is all I would go, however Intel rates that cpu for a max of 1.55 so it is your call on where to draw the line.

With the memory you have, where you are now (1600) 1:1 , cpu at 2.8 memory at 800 is pretty good and it will take a lot of work to get much more. You can likely get a few more MHz of FSB before your memory limits you but then it is going to get tough.

 

[mdahu]

The synced mode and 1:1 mode confused me too. I always thought they were the same. But I have an ASUS P5N-E SLI, similar to yours, and in the bios where you set the FSB as linked, there are two seperate choices. 1:1 and synced. Synced mode halves the memory speed.

Also, would having faster memory allow you to overclock the processor further? I was thinking of upgrading my memory anyhow and the difference in price between DDR2 at 800 or 1066 is small. I will get the 1066 if it helps, but my mother board specs says my limit is 800.

Thanks

 

[haadij404]

the e6300 has a LOW multiplier so whatever your FSB mulitply it by 7.

400x7 = 2800mhz

to reach 3ghz you need 430x7 = 3010mhz

also the mobo quad pumps the fsb so 400 = 1600 and 430 = 1720

so to keep a 1:1 divider at 3ghz you need overclock your ram by 60mhz

when i had my e6300 at 3.2ghz i had my vcore at 1.42v and the northbridge at 1.56v.

 

[BillParrish]

The synced mode and 1:1 mode confused me too. I always thought they were the same. But I have an ASUS P5N-E SLI, similar to yours, and in the bios where you set the FSB as linked, there are two seperate choices. 1:1 and synced. Synced mode halves the memory speed.

I was not aware of this bios option as I concentrate on Gigabyte boards. Interesting and most likely the one the OP wants to keep enabled so that the memory is always 2x the FSB.

Thanks for pointing that out.

 

[hstuehmeyer2000]

I was not aware of this bios option as I concentrate on Gigabyte boards. Interesting and most likely the one the OP wants to keep enabled so that the memory is always 2x the FSB.

Thanks for pointing that out.

The reason your board does not have the synced option is because you use an intel chipset. The chipset he is using is an nvidia one.