Overclocking an i7-920

I don't mean to sound dumb, but I have a few questions about bios settings. I'm running an i7-920 on an Asus P6T with 6 gb of Sorsair XMS3 pc 1600 cas8. I've just got a PNY 9800GT video card since I don't game. It's all cooled by an H50 and the fans in a Cooler Master Storm Scout case. I'm running Windows 7 Pro. I copied the settings from a couple of your posts and am getting 3.53 out of it. Some settings

Ai Overclock Tuner- Manual
Intel Speedstep - Enabled
Turbo Mode- Disabled
Multiplier- 21
BCLK Freq- 175
PCIE Freq- 100
Dram Freq- 1704
CPU Volt- 1.2875
CPU PLL Volt- Auto
QPI/Dram Core Volt- 1.25
Dram Bus Volt- Auto
CPU Differential Amplitude- 800 mV
Dram MultiplierX8 ?
UNCLK- Auto

Where is the V Dimm voltage? Is it the QPI/Dram Core Voltage? Overclocking sure has changed since the old days of cracking off the cpu case and plugging a "Golden Fingers" device with dip switches onto it!
Also, when not doing much, the multiplier drops down to 12.
Oh yeah, The main reason I'm posting is it runs great until I run Prime. After about 3 minutes, I get the dreaded BSOD. Thanks for any help!

Since you have DDR3-1600MHz RAM installed, lower the DRAM frequency from the current 1750MHz to 1400MHz. The current DRAM frequency of 1750MHz = a 10x DRAM multiplier at the present 175MHz BCLK. You'll in essence be dropping the DRAM multiplier from 10x to 8x for an effective 1400MHz DRAM frequency. Make sure to also change the UCLK Frequency to 2800MHz - 2975MHz (DRAM mult. x 2 + 1 x BCLK). And assuming the SPD timings for your RAM are 8-8-8-24, manually adjust the four primary RAM timings (adjust accordingly)...


... or try leaving the DRAM freq. at the current 1750MHz, but loosen the four primary timings to 9-9-9-24. Make sure to run Memtest86+ before attempting to boot into Windows.

Edit:

bruceb3 said:

Where is the V Dimm voltage?

Click to expand...

The option is called DRAM Bus Voltage, located in the Ai Tweaker section of the BIOS. QPI/DRAM Core Voltage (as Asus calls it) is the same as Uncore, or QPI/Memory Controller voltage.

Thanks for the reply. I dropped the dram frequency to 1443 and raised the bclk to 180 which is giving me 3.78 . Kept my timings @ 8-8-8-24 since I lowered the frequency. Prime no longer gives me a blue screen. Ran it for about 10 minutes and RealTemp GT showed my temps around 72-74. I'll try Prime for longer later, but wanted to check with you guys to see if those temps are too high.

Jeez, My C0 is at 1.4 vcore to get 4.0 ghz, and Im only hitting like 65c at max. Granted Im running a triple 120 with 120x38 san aces in push pull. Still, with such a low vcore, Im suprised your seeing those temps.

bruceb3 said:

Thanks for the reply. I dropped the dram frequency to 1443 and raised the bclk to 180 which is giving me 3.78 . Kept my timings @ 8-8-8-24 since I lowered the frequency. Prime no longer gives me a blue screen. Ran it for about 10 minutes and RealTemp GT showed my temps around 72-74. I'll try Prime for longer later, but wanted to check with you guys to see if those temps are too high.

Click to expand...

At 3.8 I am at 67C with the H50 with HT on and 53C with HT off.