adaptive Vcore question

pc-guy

pc-guy

pc-guy

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29 May 2005
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I am hoping this is more of a generic question as opposed to motherboard/bios specific one.

I want my 4770K to lower the voltage when it is not doing much in the similar fashion as it is lowering the multipliers. However I do not want it to go pass the voltage which I have used to achieve my overclocks, because I don't want it to cook the CPU.

So at the moment, I have all the C-states enabled as well as step speed. CPU Fixed mode (multiplier) is disabled so the step speed is lowering and increasing multiplier depending on the load.

But the Vcore is constant in CPUz no matter what the overall CPU frequency is. Currently I have my Vcore set to "Override" or "Manual" and have specified a value for Vcore.

Now I am thinking that it needs to be in "Adaptive" for the CPU to adjust voltage along with multiplier. But the BIOS information says "Additional Voltage" if I choose a value other than "AUTO". I also have a second option for OFFSET Vcore.

so my question is if I want a maximum voltage to be specified in Adaptive mode, do I put this value into the box?
 
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Now I am thinking that it needs to be in "Adaptive" for the CPU to adjust voltage along with multiplier. But the BIOS information says "Additional Voltage" if I choose a value other than "AUTO". I also have a second option for OFFSET Vcore.
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Not sure what mobo you have, my ASUS x99 sounds similar.

You are correct that if you want the VCore to lower when the OC voltage is not required you need to use 'adaptive', on mine I also have an offset sign (+/-), I use +.

I then put in how much extra mV in the offset box to add above the default voltage shown in a box to the left.

I don't get an exact figure of what it is starting at, but that is because I have initial voltage set to Auto, it shows slightly over 1v.

So what I did was start low (@ 0.125), then boot and run passmark to get the CPU usage up to see what the max it pushed it to.

I kept tweaking in minuscule increments until I had a stable OC which for my 5930k haswell-e was 0.195, which has it running OC'd @ 4.5GHZ and max volts 1.286.

For my chip and all the default OC's I've seen posted on the net, they all tend to just put a manual voltage of 1.3v, so I'm happy that I run my OC stable just under that with the adaptive vCore, which sometimes shows as ZERO volts?

Max temp when I ran Asus benchmark ROG tool was 68deg, which isn't bad on air as most say up to 80deg on water is good max! as the TJMax on these chips are 115deg.

Just start low and increment very slowly, you'll soon get a feel for what the likely setting is to hit your desired max volts, keeping an eye on temps at all time.

so my question is if I want a maximum voltage to be specified in Adaptive mode, do I put this value into the box?
Click to expand...
NO!!! The offset is how much to ADD or SUBTRACT depending on sign(+/-), not the actual max voltage or desired voltage. it's how much to offset on top of the default initial voltage. Well on my Mobo it is!
 
every chip will have a default cpu voltage,some higher some lower ,loadline calibration will add a certain amount of extra voltage ontop depending what level you choose

cpu offset will then add a further amount ontop of default and llc = total load cpu voltage

offset only gets applied under full cpu load so be carefull not to add too much or it will cook the cpu

always keep the first two digits as 0 in cpu offset,+0.0

+ will add voltage at load to the cpu and - will take off or undervolt the cpu default voltage (remember to fine tune the loadline calibration level so it doesn't add too much or too little)
 
I think my motherboard's adaptive Vcore is not working or rather it is just a null value.

basically whatever value i set the Vcore shots up to the default 1.28V. also I disabled PPL Overvolt or any other kind of overvolting. in order to get the volt i want i needed to dial in -ve value (quite a lot) which means my CPU is unstable when it is idling...

mobo is Asrock Z97m Pro 4, might need to raise an issue with Asrock.
 
hmm, interesting, I had to do a cold reset and just manually reset adaptive, and found the same as you it was constantly pumping the offset.

I ran the 5 way optimiser, went back into bios, none of my settings had changed but now the adaptive offset is working correctly.

I think there is another setting under advanced / CPU configuration to enable the actual CPU power management. CPU C States perhaps?

I assume you also have speed step and turbo enabled?

I'm still learning myself, so make sure you investigate what each setting does, but I myself having now experienced the same phenomenon, would also like to know what BIOS setting makes the difference!
 
yes, i have C-states all enabled which as I understands it allows the CPU to lower voltages and reduce operating current.

step-speed controls the multipliers which is definitely working. turbo had to be turned on enable >35x multiplier.

yes I am a bit stumped as well. I might do a clear CMOS and see how it plays out.

but gonna stay with constant voltage for now until i get an answer from asrock...
 
problem solved!

I disabled intel TURBO BOOST, now the adaptive voltage is behaving "normally".

well the Vcore doesn't go above my set voltage, matter of fact it is seriously undervolting by .065V which I had to dial in on the offsets...

the Intel TURBO BOOST was overiding all the adaptive settings and basically making the CPU default to maximum Vcore it can take.
 
cool, nice detective work.

I'll have to check my BIOS settings as I could have sworn turbo & speed step were enabled, yet adaptive was working.

I'll let you know once my new GTX970's arrive and are installed :-)
 
actually without turbo my clocks won't go beyond 3.5GHz which probably explains the undervolting.

so not entirely working atm.

Asrock has not got back to me on this either and it has been a while

i also use the xmp profile from CPU and the board does the same thing. adaptive voltage is unregulated ie it defaults to the maximum voltage the CPU is allowed
 
i had another quick fiddle. I realised my problem...

rather it is Prime95's problem. it draws additional volts to CPU regardless.

So now the adaptive is working as it should, I put offsets to increase the top volt to the desired and the volt drops under idle or light load.

when stress using RoG RealBench and OCCT, the volts are behaving as it should.

Very happy now. It's the VX something instructions in prime that is causing the issue. Also the load is more evenly spread and the CPU is running 150C cooler in stress as Prime was hitting mid 90sc now it is around 70C.

but only able to get 4.3Ghz on 1.2V so will see what water cooling can do and what volt this chip needs to get 4.6+
 
Still pulls a extra 0.1v if it comes across anything that uses AVX instructions. That's what caused his problem in the first place. There is just no way around it but to avoid things like P95.
 
Yep, p95 is a no go on haswell. Temps get too high and its not a good stability tester as your chip will likely be throttling under it. Asus real bench is a much more realistic test.
 
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