Voltage problem on Asus P8Z68-V/GEN3

Unknown-One

Unknown-One

[H]F Junkie
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Mar 5, 2005
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Something seems to be very wrong with the voltage control on the P8Z68-V/GEN3. No matter what I do in the UEFI, when I boot into Windows, the voltage is WAY higher than I set.

I currently have the UEFI set to 1.125v and the voltage is showing up as 1.35v in Windows.

Am I missing something here?
 
Are you setting a manual voltage, or offset? What setting do you have for Loadline calibration?
 
You need to study how offsets work.
Offsets work by adding a vcore value to the "auto" serial VID which the processor requests for that multiplier. For example, an offset of 0.100 mv should give you a vcore of 1.31v if the VID for that processor at 3.4 ghz were 1.21v. This is before vdroop, however, and vdroop combined with LLC can give you different results. The only reason to use offsets is for having the voltage drop to something like 1.15v at idle with the cpu downclocking to 1.6 ghz.

Each multiplier mhz step will give a different SVID, with the Svid going up at higher speeds, and thus your resulting voltage in windows will be based on the serial vid combined with the offset.
 
Falkentyne said:
You need to study how offsets work.
Offsets work by adding a vcore value to the "auto" serial VID which the processor requests for that multiplier. For example, an offset of 0.100 mv should give you a vcore of 1.31v if the VID for that processor at 3.4 ghz were 1.21v. This is before vdroop, however, and vdroop combined with LLC can give you different results. The only reason to use offsets is for having the voltage drop to something like 1.15v at idle with the cpu downclocking to 1.6 ghz.

Each multiplier mhz step will give a different SVID, with the Svid going up at higher speeds, and thus your resulting voltage in windows will be based on the serial vid combined with the offset.
Click to expand...
I know how offsets work, but this isn't making any sense...

- Stock voltage is 1.2v
- Offset is -0.075
- The UEFI shows 1.125v, which is the expected value for this offset.

Boot into Windows, and suddenly I'm running at 1.35v (and spiking up to 1.4v at random when under load)... I don't get it. How do I fix this?
 
Unknown-One said:
I know how offsets work, but this isn't making any sense...

- Stock voltage is 1.2v
- Offset is -0.075
- The UEFI shows 1.125v, which is the expected value for this offset.

Boot into Windows, and suddenly I'm running at 1.35v (and spiking up to 1.4v at random when under load)... I don't get it. How do I fix this?
Click to expand...

The stock voltage isn't fixed. So in the BIOS your VID is 1.2V, but under load (in Windows), the VID might be 1.375, so with your offset that would give you 1.3V. What speed are you running? Why not just use a fixed voltage until you get it dialed in?
 
Fixed voltage didn't respond as expected either.

I'd set 1.3v in the BIOS and would be stuck at 1.2v in Windows still...

Edit: I just reset to optimized defaults, and now things are even goofier. The processor is running at 3.7GHz while idle and 3.3GHz under load... that seems totally backwards. It used to run 1.6GHz while idle and 4.4GHz while under load.
 
cisco guy said:
just flip on the TPU switch reboot twice and be done with it
Click to expand...
Yeah, that wasn't great advice. I gave the automatic TPU thing a shot, it gave my 4.3GHz and it decided to juice my CPU with 1.45v (I've never trusted automatic overclocking before and this is a big reason why). I very quickly shut the system down and cleared its settings. I have things dialed back down now, I just hope the motherboard didn't damage my processor...

I turned off Turbo mode, disabled SpeedStep, and then set it to use manual voltage. The board is FINALLY acting predictably, and responding to both voltage and multi correctly. I'm currently up to 4.4GHz at 1.295v

I'll get my overclock dialed in, then try and get SpeedStep working with it so I'm not running in excess of 4GHz while idle... any tips on how to make that work?
 
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1.45V Vcore thats impossible with TPU after rebooting into windows twice like I said
The 4.3 result always becomes ~ 1.285 load, <1.0 idle.in CPUID
Manually changing multi to 46 still only 1.35V load
Thats with over 150 mobo
Some other CPU setting was borked
But if you are happy now, then thats all that counts

Please note voltages
48 multi IDLE
YI5oc.jpg

48 Multi LOAD
N41RD.jpg
 
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Unknown-One said:
I'll get my overclock dialed in, then try and get SpeedStep working with it so I'm not running in excess of 4GHz while idle... any tips on how to make that work?
Click to expand...

Should be as simple as turning EIST and C1E back on. Power-saving and overclocking work pretty well together with SB. If you are using a manual voltage it'll stay at that even when downclocked, but that's not a huge deal. You'll have to go back to offset to get it to both downclock and downvolt.
 
There's a really good written and pictorial guide in the motherboard forums on the P8Z68 motherboards which show how to easily get to 4.8Ghz (if your chip can do it). I can't find it atm, but do a search and it will pop-up.

I ended up dialing my 2600k machine back down to stock settings except for the boost multi up to 46.
 
K1tty said:
There's a really good written and pictorial guide in the motherboard forums on the P8Z68 motherboards which show how to easily get to 4.8Ghz (if your chip can do it). I can't find it atm, but do a search and it will pop-up.
Click to expand...

Can you link me to this?? :)
 
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