i5 2500K overclock VID difference question (PICS)

Space Monkey

Space Monkey

Space Monkey

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Hi all,

I've just overclocked my i5 2500K to 4GHz by changing the multiplier (is this the correct way to overclock the i5?)

But my main question is that on CPU-Z the Core Voltage is 1.25ish, I set 1.25 manually in the BIOS, but on Real Temp it shows the VID as 1.33-1.37, is this the same as the Core Voltage, and if so why is it a lot higher?

I'm hoping to try and keep the Voltage down on the CPU so that the temps are lower?

Any help would be greatly appreciated :)

nb9k4y.jpg
 
VID and vcore are two different but related readings.

Looks like the voltage is set at offset which is why you have two different readings, the one CPUZ shows (1.256v) is the voltage you are operating at.

If you were to set the voltage as full 'manual' then the VID and vcore would be allot closer if not identical.

And yes upping the multi is the correct way of overclocking your chip.
 
pgi947 said:
VID and vcore are two different but related readings.

Looks like the voltage is set at offset which is why you have two different readings, the one CPUZ shows (1.256v) is the voltage you are operating at.

If you were to set the voltage as full 'manual' then the VID and vcore would be allot closer if not identical.

And yes upping the multi is the correct way of overclocking your chip.
Click to expand...

I think hes specified a manual voltage to 1.25, the VID reading is from the cpu so that does not change, manual sets the voltage to one constant voltage while offset minus or subtracts from the requested VID. Offset is better as that allows lower voltage when idle instead of a constant high voltage.
 
Thanks guys,

I ask mainly as when I was running IBT, the Real Temp reading of the VID was increasing inline with the temps going up, but the CPU-Z Core Voltage basically stayed static, so can I as pgi947 says, set the BIOS voltage to full manual and thus lower the VID, to match the Core Voltage of around 1.25, so that the temps will lower (subject to system being stable?) or is there more to it?
 
You are not running any higher than 1.25v, your temps are going up with load, not as a result of the VID. The VID is what the cpu 'wants' not what its getting. Setting a static voltage is not the best way, offset is.
 
Justintime said:
You are not running any higher than 1.25v, your temps are going up with load, not as a result of the VID. The VID is what the cpu 'wants' not what its getting. Setting a static voltage is not the best way, offset is.
Click to expand...

Ah right, so its just saying give me 1.35 but I'm saying no, you can only have 1.25, yet it still runs fine on the lower voltage?

So should I go back into the BIOS and set the Core Voltage back to auto, and then use the offset to lower back to 1.25? If so, how does the offset work in the BIOS, ie what values should I be entering?

Thanks again for your time chaps :)
 
Its a matter of tuning it.. an offset of say +.05v may result in a vcore of 1.3v in one cpu at 4GHz and 1.278v in another cpu of the SAME model at 4Ghz, as VID is different in different chips.
 
So should the Core Voltage be set to auto?

And then use the offset? And should I be using negative offsets to lower the Core Voltage? I'm assuming the offset is related to the current VID requested from the CPU? so to undervolt the CPU I need to use negative offsets, and positive offsets to overvolt for higher overclocks?

[edit] all things being equal, as you say there may be some differences due to my setup vs someone elses?
 
I don't think the offset can be worked with a static manual voltage, so auto is likely what you need to set it to, negative will lower yes. Each chip is different in that its overclocking potential at a given voltage will vary and the VID requested will as well, one cpu may do 4.8Ghz at 1.35v whereas another may need that to break 4.4Ghz.. one chip may need default 1.05v for the VTT to run 16Gb of RAM whereas another may need 1.1v as its got a weaker memory controller.. etc.. . Even components in your motherboard can vary with another of the same model.
 
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No problemo, have fun! Keep it under 1.38v or so and you should be fine (some say more, some say less, but thats my opinion on the matter lol)
 
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