BIOS vs. CPU-Z & Easytune6 CPU VCORE?

[xxpharoahxx]

ok i have a dilemma... in bios i manually adjust CPU VCORE to 1.35000. although when i open easytune 6 and cpuid & cup-z they all say 1.26v? is this correct? But in easytune 6 when i switch to the voltage advance tab i see that it properly lists CPU VCORE as 1.35000.

[morph]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

That's called vdroop. It's an Intel specification designed to protect your CPU from overshooting voltage. Usually it's somewhere at 0.05-0.06V. I never thought that UD3P could have such high vdroop. I take it you have LLC disabled. You could try enabling LLC if that disturbs you, and in this case you could possibly lower vcore to about 1.3V or even lower, if you chip is fully stable @1.264V at that clock.

[Psycho101]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

Agreed with the above. That's alot of droop though. My UD3P doesn't droop as much.

To make sure everything is as it should be, go into the BIOS and enter the PC Health section. It will list the current Vcore etc along with the current voltage being received from the PSU's 12V rail. The 12V rail (not to be confused with a -12V or minus 12V rail) is the line that power is taken from, then stepped down by VRM circuitry to reach your required Vcore.

Take a look at the reading for the 12V rail. This voltage has a tollerence (as per the ATX specification) of +/- 5%, so the minimum it should be is 11.4V and the maximum is 12.6V. If it's within that range then all is OK.

Unless you have stability problems however, I would not enable LLC. It's safe to use IMO, but it does put your CPU "out of spec". As morph said, it's designed to make sure that no matter what happens, your Vcore never goes past what you set in the BIOS. It can in some circumstances cause voltages to briefly spike upward. This isn't much of a problem at lower Vcores but the higher the Vcore, the higher the spikes.

A rule I like to follow, and one that's IMO quite sensible is that if I can get stable at my desired clock speed with 1.3625V or below without LLC I do so. If I find I need more voltage than 1.3625V (the maximum VID a 45nm could possibly have, and where Intel's warranty ends if exceeded) then I enable LLC and try to get stable starting at 1.3500V, then work down if stable, or up if not.

[xxpharoahxx]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

ok i have some upsetting news atleast for me anyways. If the problem is Vdroop i am very well stumped because i checked my bios and i already have LLC Enabled, it's one of the first things i enable in bios. Although i took a pic of my PC Health screen. What could be the cause of this Vdroop, should i try default settings and see what happens?

[Psycho101]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

It could just be Vdrop. Unlike Vdroop, this isn't "fixed" by LLC.

Does your Vcore decrease in CPU-Z when you click start on prime95, ie does it droop any at load?

Your PC health voltage figures look fine. It's not as accurate as using a multimetre and testing molex/p8 connectors etc by hand but it's an OK indication.

you could always eliminate any BIOS issue by writing down all your settings (don't save a profile as on reloading it you may restore dodgy BIOS settings with it), re-flashing the current version and then loading optimized defaults, then save and exit. Re-enter your settings with LLC on and see if it's lowered the amount of Vdrop.

[xxpharoahxx]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

Reflashed Bios and upgraded from UD3p.f9 to UD3p.f9l oced to 3.8 which is nothing for this chip and it's 100% stable in prime 95. But when i look in pc health it still sais VCORE 1.216. Maybe it's always said that and i just haven't realized but not sure. I also def. enabled LLC and i can tell LLC is on because the core speed doesn't fluctuate in cpu-z. So this is normal?

[Psycho101]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

Yes, it's normal. Motherboards can have varying levels of Vdrop (difference between set Vcore in the BIOS and the actual voltage supplied. Your board has by no means a huge Vdrop problem, but it does drop more than mine. There may be just as many others who have the same level of Vdrop, or maybe a bit more than you. I'm positive there's nothing wrong with your board.

You seem to be doing pretty well with overclocking too, which indicates to me that everything is working within an acceptable range.

[xxpharoahxx]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

i see... hmmm so should i pay attention to the cpu-z vcore because that's what's actually running or the bios vcore? ie. if i needed 1.38000 vcore in cpu-z i would need to put 1.40000 in bios.

[Psycho101]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

I go by the CPU-Z reading to see what my processor is actually receiving. However as far as going over any voltage specifications eg a 45nm dual core chip's max voltage of 1.3625V, I tend to err on the side of caution and use the PC Health reading. I believe that as PC Health shows slightly higher, I have a little safety margin. If quoting voltages used though I do usually quote CPU-Z shown volts, like in my sig, 1.425V is the CPU-Z figure.

[xxpharoahxx]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

wow. this was definitely the culprit that was holding me back in my previous oc' of 4.3ghz stable. Now i'm testing with same oc' and my "real" vcore is 1.34 no errors so far with orthos been running for 24 min as we speak.
I will continue to lower bios vcore and monitor how low i can get cpu-z vcore stable with the 4.3ghz oc.
Knowledge truly is power ... just wish i had it earlier lol.
again pyshco thnx... until i need another plethora of info

[Psycho101]

Re: BIOS vs. CPU-Z & Easytune6 CPU VCORE?

Good to see you're having some success. As usual, watch those temperatures. Keep CoreTemp or realtemp running in the background. RealTemp will show you the peak temps your cores reach, which is really useful. 60c is good, 65c is ok, but anything over 67c-68c is about on the limit.