I7 920 D0 VCore readout

[itsgrandpa]

Hey guys,
I've been playing around with my i7 920. I was able to get a modest 3.4ghz @ 1.100 volts. Today I bumped the Vcore to 1.200 and i have a stable 3.8ghz that's been stressing for 7 hours now (oddly its at the same temps @3.4ghz)

In my BIOS I set the Vcore to 1.200. But at 100% load, CPU-Z is showing my core voltage is @ 1.144.
Am I able to drop by BIOS Vcore just above the threshold of the CPU-Z reading?

For reference, I did not enable Load-Line Calibration.
Thank you.

 

[itsgrandpa]

When the multiplier bumps to 22.0 I reach 4.0 gigahertz.

 

[Rustyy117]

Your seeing the effects of Vdroop

If you would like to know what vdroop is, have a read here: http://www.thetechrepository.com/showthread.php?t=126

To answer your question, No you cannot adjust the BIOS Vcore to match (or be slightly higher than) the CPU-Z Vcore reading. Though you could increase load-line calibration to lessen the effects of Vdroop

 

[legendkiller]

There's no 22x multiplier in a i7 920, there's only 21x in 920...
Put your CPU at 21 multiplier and put BCLK at 191 which is 4GHz and put your VCORE at 1.34v

 

[robustus64]

my i7 920 liked 1.40.

 

[Rustyy117]

If OP's CPU is stable at 3.8Ghz with 1.2V then I doubt it would need 1.34 or 1.40V for 4Ghz...

 

[itsgrandpa]

Dropped Vcore to 1.8125

I'm not sure but mine occasionally hits 22x

It seems CPU-Z and CPUID Hardware Monitor readings are not very accurate. Is there another monitoring system that someone would recommend.

Wow thank you Fatal, I'm reading the post right now... very informative!!

Also to clarify, is the actual voltage closer to what I set in the BIOS (1.20v) or what the readings from CPU-Z/CPUID HW monitor (1.14)

 

[legendkiller]

Software are not accurate, cant solve that... AIDA64(Which is the best in my opinion) shows 1.328v awhile in BIOS it's 1.34v...
How is it possible for you to get 22x multiplier??????? Also how did you even get 3.9GHz with 1.18v? You must got the best processor(In i7 9xx)... I hope you can show us if you can get 5GHz with 1.4v-1.44v

EDIT: You can use HWMonitor which should show your Vcore voltage when run max... So far HWMonitor is showing 1.34v for my voltage...

 

[Rustyy117]

CPU-Z is generally pretty accurate, its just really differcult to get the same Vcore value in CPU-Z as you have in the BIOS as your motherboard would need very high quality power phase design and 100% LLC.

I think (not 100% sure) that the value in CPU-Z is what is being pushed through your CPU rather than what its set in the BIOS.

Oh and well done on your overclock, although you haven't got HT on, its still a very good CPU, my old Core i7 950 needed 1.41V for 4Ghz

 

[itsgrandpa]

@omgitzfatal Everything you said is on point. I turned HT off since I only play SC2 which does not utilize the extra threads.
I finish reading the post on Vdroop... twice ... I'll assume since I don't have a background in EE may be partially why I had difficulty understanding it.

I may be talking out of my rear but what I got from it was Vdroop creates an upper and lower bound providing a narrowed window of voltage to feeding stable power to the CPU. (okay, i really didn't understand it at all, please correct me)


Ran AIDA64 - seems consistent with the other programs.

 

[legendkiller]

Try to get 5GHz @ 1.35v ...

 

[itsgrandpa]

I was playing around with the Vdroop but didn't like it since it left the possibility of frying my CPU and the power occasionally cuts out randomly at my college.

Looks like 3.8 is the sweet spot =(
3.8 @ 1.6 volts <50C
4.0 @ 1.9 v <60C
4.2 @ 2.2125 v <65C

Temps stayed below 50 at 3.8 with HT off. 4.0 kicks it near the 60's range which is a bit high for me.

 

[legendkiller]

I was playing around with the Vdroop but didn't like it since it left the possibility of frying my CPU and the power occasionally cuts out randomly at my college.

Looks like 3.8 is the sweet spot =(
3.8 @ 1.6 volts <50C
4.0 @ 1.9 v <60C
4.2 @ 2.2125 v <65C

Temps stayed below 50 at 3.8 with HT off. 4.0 kicks it near the 60's range which is a bit high for me.

Try 5 GHz at 1.35v or lower lol... You probably got the Best CPU ever in the world to reach 5GHz with such low voltage and it's even the first Gen. too LOL...