Haswell CPU VID redo, let's try this again

Hulk

Diamond Member
Oct 9, 1999
5,189
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I have an old thread here where I'm asking people to submit their VID and best, stable overclock. As many in that thread pointed out to me there were too many variables for a meaningful comparison.

So I want to try it again with a specific test procedure. The point being to see if there is a definite trend between VID and overclocking success.

Since VID is very hard to know let's do this. Download CPUz 1.64 here
http://www.cpuid.com/downloads/cpu-z/1.64-64bits-en.zip

Under load this version will show a Vcore that is 0.018 higher than what is set in the BIOS. In the BIOS load default settings, don't change anything.

Then run Prime 95 "Blend" and report the CPUz 1.64 CPU voltage.

Also report your best overclock that is Prime 95 stable for at least an hour and your CPU.

My 4770k is a dud.
CPUz 1.64 reports 1.20V (sometimes fluctuation to 1.188 momentarily).
Let's call it 1.20 - 0.018=1.182 VID (let's call it approximate VID), which is quite high.
My best stable overclock is 4.2GHz at 1.248 Volts Vcore. I could probably get 4.3GHz with more Vcore but it's not worth it to me.

You can also report your approximate VID without a "K" Haswell, just not an overclock. Still it would be interesting to see if the "K" chips have lower Vcores at default settings than the non "K" parts.
 

Burpo

Diamond Member
Sep 10, 2013
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The variable here is the boards power section. Just because yours shows .018 difference in voltage doesn't mean others will. Every board's different and VRM's fluctuate. No 2 boards are identical..
 

Hulk

Diamond Member
Oct 9, 1999
5,189
3,808
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The variable here is the boards power section. Just because yours shows .018 difference in voltage doesn't mean others will. Every board's different and VRM's fluctuate. No 2 boards are identical..


There may be some variability in boards of course but at least we have a procedure to get this value.

I'd like to see some data. We'll know relatively quickly if it's meaningful or not.
 
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BallaTheFeared

Diamond Member
Nov 15, 2010
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Inferno Mode!!!!!!!!!

hot_zpscc7d370d.png~original


Bios reports 1v for stock vid.
 

BallaTheFeared

Diamond Member
Nov 15, 2010
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Dark Knight II with two Corsair SP 120s in p/p...

Never did delid, you can see why :)

That actually had Diablo 3 PTR up in the background, playing on my HD4600 overclocked to 1500MHz on the stock voltage and my DDR3 undervolted at 1600MHz...

She be sipping power, 60w or less with vsync disabled...

New vid should be here today, will be painful to see the kill-a-watt after having sub 30w idle and 60~w load for a week now :|

Edit: Non AVX game load... With the iGPU at 1500MHz 0.9v

temps_zpsd645f71e.png~original


SYSFAN and CPUFAN are the corsairs (only two fans I've got!).
 
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ChronoReverse

Platinum Member
Mar 4, 2004
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As an aside, Prime95AVX's blend mode doesn't really heat the CPU that much. SmallFFTs will give you another 20c
 

thilanliyan

Lifer
Jun 21, 2005
12,065
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I haven't really tried much, but I think I am P95 small FTT stable at 1.248v for 4.1GHz. I'm watercooling too but the temps still get to around 80C according to XTU which is at the limit for how far I want to go.

I will stay at stock for now...not doing anything intensive anyway plus I have no time to tweak until February probably so will try then.

EDIT: P95 Small FTT really heats the CPU. Even Aida stability test doesn't take things that high.
 
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ChronoReverse

Platinum Member
Mar 4, 2004
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Okay. My i7-4770k gets 1.188v (under full full).

It can hit 4.3GHz (smallFFTs AVX stable) when set to 1.165v

Hmm, I'm not sure the CPU-Z method is reliable. I checked in my UEFI and it says 1.044v

@Hulk
What does your mobo say?
 
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OCGuy

Lifer
Jul 12, 2000
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In order for this to be a tad more helpful, including the batch number for the chip would be a good idea.

Even though this is not exactly a scientific survey, it is possible to see patterns within batches if we get enough responses. I have a new 4670k to unbox and will see what happens.