Core i7 920 D0 overclocking - BIOS and CPU-Z show different processor voltages.

[konstantin90]

Hello everyone, first post on guru3d forums. Been reading news and reviews from here for years now, never really thought about joining the forum.

Recently got my new system with Core i7 (full specs should be shown somewhere), done a lot of research on overclocking the new way and ended up with the following:

CPU @ 3.6 Ghz
CPU Multiplier - x18
Base Clock - 200 Mhz
QPI - 7.2 GT/s (3600 Mhz)
QPI Multiplier - x36
UnCore - 3200 Mhz
UnCore Multiplier - x16
Turbo - Off
SpeedStep - Off
HT - On
RAM @ 1600 Mhz
RAM Multiplier - x8
RAM Timings - 8-8-8-24-1T
CPU Vcore - 1.20V
QPI - 1.30V
RAM - 1.60V
All rest on Auto
All power saving options disabled

Ran Prime95 (large FFTs) for around 20 minutes, seems stable.

So the problem is that I already set my CPU voltage extremely low for this overclock (usualy I see people at 1.36-1.45V), CPU-Z is showing it at 1.12V, which is miles out to what it should be at.

Of course it is a good thing to have such low, stable voltage, however I do find it as an issue to be so different. Also it seems to jump (according to CPU-Z) from 1.120V - under load and 1.152V - when idle, completely different to what you would expect.

Does everyone get the same effect? Is it my power supply?

What is your opinion on this?

Thanks.

P.S. Any tips / suggestions on my overclocking are most welcome.

[Psytek]

I've never had a MB which hit the target VCore, its always going to be less in windows.

Also, mine fluctuates too, you just have to make sure the minimum voltage it goes to is enough for your OC:

[morbias]

It's meant to be like that. There are three states the vcore will be at. The load voltage will be the lowest because of vdroop (the difference between idle and load), then idle voltage (after vdrop/voffset), the BIOS voltage is the limit or ceiling to prevent overshoot damaging the processor.

The reason these different states are needed is because the VRMs on the motherboard cannot switch from one voltage to another instantly.

[konstantin90]

Thanks a lot, that clears most things.

[macdaddy]

you got a gigabyte board thats why they mave massive vdrop. i know cause i have extreme version of your board.

[lmimmfn]

ive my vcore @ ~1.28v for a 4Ghz overclock( its at 1.24v now, im not rebooting just to check lol )

[chronicbucks]

dude, thank you so much for posting your Bios, i have the UD4p board, and was struggling to find a good overclock, i had the CPU at 3.8, but in doing that, i had to run my RAM at 1066. HOWEVER, after applying your BIOS to my system, and changing the bclk from 180 to 190, i now have 3.8ghz, 7-7-7-24 1600mhz RAM. Ran prime95 for 2 hours, no issues

was getting temps around 38 idle 63 peak. Went back into BIOS and turned on the power saving functions. Now im idling at 35 (10 above ambient) and full load at 61. PERFECT, i saved my BIOS and probably wont touch it forever

i cannot begin to thank you Konstantin. I had been messing and reading and tweaking for weeks, and then i stumbled upon your thread, and BAM, light at the end of the tunnel. Thank you buddy for providing me with the perfect BIOS settings to overclock and get the most out of my RAM at crazy low temps

gotta love the d0....requires so little voltage!

[konstantin90]

Originally Posted by chronicbucks

dude, thank you so much for posting your Bios, i have the UD4p board, and was struggling to find a good overclock, i had the CPU at 3.8, but in doing that, i had to run my RAM at 1066. HOWEVER, after applying your BIOS to my system, and changing the bclk from 180 to 190, i now have 3.8ghz, 7-7-7-24 1600mhz RAM. Ran prime95 for 2 hours, no issues

was getting temps around 38 idle 63 peak. Went back into BIOS and turned on the power saving functions. Now im idling at 35 (10 above ambient) and full load at 61. PERFECT, i saved my BIOS and probably wont touch it forever

i cannot begin to thank you Konstantin. I had been messing and reading and tweaking for weeks, and then i stumbled upon your thread, and BAM, light at the end of the tunnel. Thank you buddy for providing me with the perfect BIOS settings to overclock and get the most out of my RAM at crazy low temps

gotta love the d0....requires so little voltage!

Hi, I didn't intend for them settings to be shown as an example, but I'm glad it helped you

Enjoy your Core i7, it really is an amazing processor.

[GC_PaNzerFIN]

I am running Prime at 4.1GHz HT on temps under 80c.

[Jonny Manc]

OP - Do you have LLC (Load Line Calibration) on??
That should level it out a bit more.....it did for me (I have mine set to 1.15v in BIOS and register the same volts in windows as you)