Vcore not being reported correctly..i think

[eojinlim]

Here is my situation. The vcore I set in BIOS is 0.05v MORE than actual vcore as shown in cpu-z and pc probe.

I am pretty sure the vcore stated in pc probe and cpu-z is correct because the temperatures seem just about right at those vcore.

For example. I set vcore in BIOS as 1.35 but in actuality, it is actually 1.30. The temperatures are 30C/55C (idle/load) and that seems to be the sort of temperature everyone is getting with a good hsf.

What I am wondering about is why the discrepancy and should I be particularly alarmed by this?

 

[Accord99]

You're probably seeing "vdroop". Intel specifies that as the amount of current used by the processor increases, the vcore should decrease. So if you were to run a program like P95, the vcore should drop even more.

 

[eojinlim]

Should I be worried about vdroop and if so, what would be the absolute delta change my cpu can tolerate?

Edit:At the moment, my vcore drops from 1.304 to 1.272 with my e6300 overclocked to 3.44ghz.

I got exceptionally lucky in getting an e6300 that does not require as much vcore to overclock.

 

[Accord99]

It should only matter for extreme overclocks (3.6+). Based on Intel's specifications, at 3.4GHz you should see a drop of at least 0.11v from your BIOS value. See page 23 of:

http://download.intel.com/design/processor/datashts/31327803.pdf

 

[eojinlim]

So if I was setting my vcore in BIOS at 1.325 (stock voltage) but it reports it as 1.275, what is the correct vcore? I want to run my system at default voltage but when i do set it at 1.325 it goes down to 1.275 even without overclocking.

According to cpu-z, my vcore is being reported as 1.320 when my e6300 is overclocked to 3300mhz.
So is my voltage at 1.370 or 1.320?

Would I do any harm if I put more voltage into my processor? More specifically, should i set in BIOS vcore of 1.500 because the actual voltage (in cpu-z) is the "safe" maximum of 1.45 and overclock like that or should I set BIOS vcore at 1.45 and just overclock like that?

Ultimately, I want to see my maximum overclock at 1.45 and I do not know exactly what to set my vcore at in BIOS.

 

[tcG]

It's a combination of vDroop and a CPU-Z error. CPU-Z doesn't report C2D voltages correctly.

That being said, the voltage you set in the BIOS is really around .03/4v lower at load. If you're interested, there are resistors on the motherboard you can short out with a pencil to "fix"(...it's a pointless safety feature implemented by Asus) this problem.

 

[eojinlim]

Oh, so basically, what I set in BIOS is the actual voltage and the voltage that i see on cpu-z is incorrect reporting of the vcore? I am not sure if cpu-z is reporting it incorrectly because Asus PC Probe reports the same voltage on IDLE.

So should I just follow the vcore I set in BIOS? I've been making a chart tracking my overclocking and I was getting a little worried about my voltage.

 

[VirtualLarry]

I've seen this happen with a friend's A64 rig. CPU-Z is reporting the vcore incorrectly. The CPU had a default 1.35v, and even setting the vcore in BIOS to 1.4v, CPU-Z would still show something around ~1.3v. But booting into the BIOS and going to "PC Health" showed the correct BIOS Vcore.