RAM overclocking only to reach 1333MHz?

SkaarjMaster

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I'm turning on this system tonight out of the case to test first and noticed the CPU and MB can run at 1333MHz no problem, but the RAM is only rated for 1066MHz (at 5-5-5-15, 2.1V). I was wondering if it was possible or even worth it to try and overclock the RAM only? Here's my partial new system specs:

CPU: Intel Core2Duo E8600 Wolfdale (3.33GHz, 1333MHz FSB)
MB: Gigabyte GA-EP45-UD3P (FSB 1600/1333MHz, mem standard DDR2 1333)
HS: Noctua NH-C12P
RAM: Corsair 4GB(2x2GB) 240-pin DDR2 SDRAM 1066 (PC2 8500) TWIN2X4096-8500C5
VIDEO CARD: EVGA Nvidia GTX 280 (1GB)
PSU: Enermax Revolution85+ ERV850EWT 850W
HD: Western Digital Black WD1001FALS 1TB 7200rom 32MB cache SATA 3.0GB/s
DVD-ROM: Asus E818A3T Black SATA 18X
FLOPPY DRIVE: Sony Black OEM
CASE (will be): Lian-Li PC-71B full-tower

(2nd HD will be identical, external HD not listed, no DVD burner yet, no sound card added yet either; all will be gradually added)

Thank you.
 

bigwooly

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cpu/MB(at least with how you are refering to it) are quad pumped.

cpu fsb = 4 x actual FSB

ddr ram is exactly that Double Data Rate

ram speed = 2 x actual FSB

Now there are all kinds of different Ram:FSB ratios/multipliers however from what i've read you gain no real benefit from running anything higher than 1:1. (correct me here if i'm wrong)

so with your setup

1333/4 = 333 actual FSB
1066/2 = 533 MHZ (thats the highest actual FSB your ram is raated for)

So you will actually be underclocking your ram if you run a 2:1. or on another note you have lots of headroom for a nice overclock.
 

BillParrish

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I agree.

And it will not hurt anything to run a 4.0 memory multiplier which will set the memory at 1066 with a 333MHz FSB.

Once you are happy with proper operation at stock (10x CPU multiplier x 333 FSB) = 3.33GHz CPU speed.....

you might try setting the Vcore to 1.35v, VMCH +.1 and see if you can get it to run at 9 x 400MHz FSB with a memory multiplier of 2.5. That would be a mild OC of 3.6GHz vs the stock 3.33 but the higher FSB speed will help you take advantage of your higher speed memory even if the memory is slightly under-clocked at 1000MHz compared to the 1066 setting.
 

SkaarjMaster

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I'm not sure about all this multiplier talk, but I let's just get it running at stock correctly before I try doing anything with increasing RAM speed. I really don't want to overclock the CPU or the FSB, but just wanted to change RAM settings to match. Anyway, back to stock settings questions, I got into the bios last night and it looks like all components are working for now (HS fan spinning, video card fan spinning and card gets hot after a while, etc.). I did get some strange settings in the bios initially and I'm not sure how to change them. Here's what I have and let me know what I need to change for stock settings for my CPU/MB/RAM (expected settings and comments off to the side after the >>).

CPU Clock Ratio: 8X >> I was expecting 10X
Fine CPU Clock Ratio: +0.5 (that means 8.5X total)
CPU Frequency: 2.83GHz (333x8.5) >> I was expecting 2.66GHz (266x10)

Memory Frequency: 1066 for SPD and Auto >> kind of expected

CPU Vcore: 1.25000 >> I believe this is what the E8600 runs at but not sure.

MCH/DRAM Reference: 0.900 >> bios manual shows 0.750

I wonder what happens if I set my DRAM Voltage to 2.1 and reboot?

The Advanced Timing Control page (tRRD through CMD) shows 4,4,8,68,4,0 right now >> seems a little higher than what's shown in bios manual (I believe I need to set the CMD to 2T here for my RAM)

Can I just go in and set the DRAM Voltage to 2.1 and the CMD to 2T and reboot or do I have to manually set other settings as well? I already know I should also set 5-5-5-15 for my RAM. Thank you.
 

BillParrish

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This should help a lot. It explains most of the gigabyte bios settings. You dont want to follow any of the suggested setting for votlage etc as your board differs slightly and the wolfdale uses lower voltages but it will give you a very good idea of what does what.

http://hardforum.com/showthread.php?t=1373759

As to your specific concerns.
CPU Clock Ratio: 8X >> I was expecting 10X
If C1E and EIST (Enhanced Intel SpeedsTep) are both enabled during light cpu loads the cpu multiplier will be reduced to save energy. You can disable both for now as it is very confusing to figure out what is happening with your cpu mulitplier and cpu voltage changing while you try to figure things out. Later you can enable them - the PC will almost instantly jump ot full speed if you fire up a game or something that really needs the cpu working full speed. You can watch the machine react by running somethign like CPU-ID utiliy and then firing off some load testing sofware like Orthos or OCCT.

Memory Frequency: 1066 for SPD and Auto >> kind of expected

yep yep all is well the system has discovered your rated ram speed and set the memory mulitplier to run it at its rated speed.

CPU Vcore: 1.25000 >> I believe this is what the E8600 runs at but not sure.

Yep yep, every cpu is different but thats about right and it will change based on load. The cpu actually has the ability to request the motherboard change the cpu voltage as needed so this will move around a little.

MCH/DRAM Reference: 0.900 >> bios manual shows 0.750

The manual is (likey incorrectly as your board only supports DDR2) showing the value for DDR3.

Per the Intel data sheet for the P45 MCH:

Symbol Parameter Min Nom Max Unit Notes
Reference Voltages
DDR_VREF DDR2 Reference Voltage 0.85 0.9 0.95 V
DDR_VREF DDR3 Reference Voltage 0.70 0.75 0.80 V

I wonder what happens if I set my DRAM Voltage to 2.1 and reboot?

Nothing should happen to the reference voltage if the board is working correctly, Your ram will run at 2.1V but since it seems stable and happy at the stock voltage there is no need to raise it. Actually I would add +.1 volts just for stablity (Total 1.9V) and to make up for any slight undervoltage from the boards memory power supply, but thats me. Corsair warranties XMS DDR2 up to and including 2.1V for life. Over 2.1 you are on your own

The Advanced Timing Control page (tRRD through CMD) shows 4,4,8,68,4,0 right now >> seems a little higher than what's shown in bios manual (I believe I need to set the CMD to 2T here for my RAM)

Thats fine for now. The bios manual cannot know what memory you are using and is for example purposes only. Take absolutely no heed to bios manual example values. It is a guide on the general principles of entering the unique values of your memory not a hard example of what should be seen. With timings set to auto the motherboard is reading the timing values stored on the memory sticks SPD (Serial Presence Detect) chip and setting the board up automatically. The best thing you can do is see if "Memory Performance Enhance " (it might be worded differently in your bios) can be set to "FAST" or whatever the next performance setting above "Normal" is.

Ignore the "Command Rate" it is, well I dont know what to call it, Intel chipsets cannot run at anything other than a 2T command rate and you can mess with that setting all day and it will do nothing. Go ahead and set it for 2T. It will look correct then.


Can I just go in and set the DRAM Voltage to 2.1 and the CMD to 2T and reboot or do I have to manually set other settings as well? I already know I should also set 5-5-5-15 for my RAM. Thank you.

Yep you sure can. At the absolute worst the machine will fail to boot with the new settings and go through the designed in "watchdog" mode of powering down and rebooting several times trying to determine the best settings to accomodate your changes, If it cannot it will after several cycles reset everything to defaults and boot up pure stock with all speed related settings on auto or disabled.
 

SkaarjMaster

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OK, I'll try it out tonight. Here are the settings that I'll change for default directly related to my "problems":

- set DRAM Timing Selectable to Manual and set the standard timings to 5-5-5-15
- set the Command Rate (CMD) to 2T (just for my piece of mind)
- set DRAM voltage manually to 1.9 (some guy online actually set this to 2.08, I wonder if this gets it out of the danger range):)
- disable CPU Enhanced Halt (C1E)
- disable CPU EIST Function

- set Init Display First to PEG
- set SATA RAID/AHCI Mode to AHCI
- set SATA Port0-3 Native Mode to Enabled
- set CPU Warning Temperature to 70 degrees C
- enable CPU FAN Fail Warning
- disable CPU Smart FAN Control

? - what about HDD SMART capability? I used to always set this to enable, but I read something online recently that said this should be disabled for better performance.

? - I'll leave C2/C2E and C4/C4E State Support disabled for now, but are they worth messing with at all?

? - in the past I usually disabled all functions that allowed the bios to assign IRQs and let the OS do it as well as setting PnP OS to No. WTF is with the new PnP/PCI Configurations that seem to only have options for the bios to select the IRQs?
PCI1 IRQ Assignment
PCI2 IRQ Assignment
- either Auto (bios auto-assigns IRQ....) or 3,4,5,7,9,10,11,12,14,15 (assigns these IRQs...)

I'll try all this tonight, but any comments you have on the things I'm changing that we discussed or any of my other questions would be appreciated. Thank you.
 

cpufast2

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Doubtful that you will be able to reach 1333 with the memory. Best maybe 1160 with lotsa voltage and relaxed timings. Like others have said you should use a divider and run the FSB up on the chip. Good luck!
 

sirmonkey1985

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i have the same memory and have to run mine at 2.15v w/vdroop 2.11v for it to be stable at 1066@5-5-5-15
 

SkaarjMaster

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"use a divider and run the FSB up on the chip"

I've never done this before, but once I get things stable I'll see about possibly doing something like this. I will need to know all the settings to change once and if I try this though. Ok, so I'll see if I have the bios version I want and then change some settings and see how it goes. Thank you all.
 

cpufast2

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When I said use a divider I meant a memory divider so that you would not max out you memory. Do a google search on overclocking your chip. You should get several hundred thousand hits in addition to the good information already provided. You should be able to find a guide for doing it. It will require some trial and error.
 

SkaarjMaster

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Well, looks like it worked and I'm running at the settings I want right now as I wanted to above (10x, 333, etc.). The SPD is now showing tighter timings (something like 5-7-7-24), but the timings are manually set to 5-5-5-15. I'll look up the divider/overclock stuff later, but anyone have any comments on the other bios settings? Thank you.

One more thing: this memory is rated to run at 2.1V. I think I might just set it at 2.1 volts and leave it; although, is there anything that could possibly automatically drive it above 2.1 volts?
 

Varmint

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Now there are all kinds of different Ram:FSB ratios/multipliers however from what i've read you gain no real benefit from running anything higher than 1:1. (correct me here if i'm wrong)

It's wrong actually - you definitely benefit from higher than 1:1 settings, you want to max out your memory clock if possible.

I confirmed this with my own test in Crysis:

e5200 2.5 GHz, FSB = 200 mHz

DDR2-400 -----------------> DDR2-800
min 18.7 ----------------------------> min 17.6
avg 36.4 fps -----------------------> avg 43.0 fps

But your gains are reduced the higher you go:

e5200 3.33 GHz, FSB = 333 mHz

DDR2-667 -----------------> DDR2-1066
min 30.4 ----------------------------> min 32.0
avg 44.0 fps -----------------------> avg 44.1 fps
 

SkaarjMaster

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OK, make that two more things. Right now I have everything installed outside the case, is that bad for the video card (GTX-280) or is it OK to do this to install Windows and stuff? I'm just not sure if the video card will overheat or not because it's not benefiting from case cooling also.
 

BillParrish

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its ok to proceed outside the case, all the nice cool room air is very good. Once you close it up in a case is when the heat problems start if case cooling is insufficient.

One more thing: this memory is rated to run at 2.1V. I think I might just set it at 2.1 volts and leave it; although, is there anything that could possibly automatically drive it above 2.1 volts?

Not really, that should be good. If manually set it should be very close to what you set it and stay there. Its the "Auto" setting that sometimes sets things too high. Manual should lock it in to what you set and I know of nothing that would change it enough to matter. Its allways best ro run the lowest voltages possbile while still maintaining the settings you want and having the machine stable. Later you can run some testing programs and see if at 2.0 volts or lower you can do what you want to do and still be stable (no BSOD's or freezing etc. etc. )

All the fancy temp reporting software etc. are nice but nothing beats your finger for a quick check. If you put your finger on the side of the ram stick and can leave it there for a slow count to 10 you are good as far as heat goes. Same rule just about everything in the machine. Do keep in mind excessive voltage does cause heat which is bad but also a transistor junction can fail just from voltage stress, the temps do not have to be high for that to happen. As far as I can tell from your posts you are nowhere near any dangerious voltages.

Have fun, glad to see it coming together for you. Remember there is no big hurry and I recommend you now get it all installed and moved into the case and use it for several days to establish a baseline of performance so that if and when you start to see what it will really do you can know if you are making progress. Good notes on your bios settings and changes made and the results are a good thing.
 
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