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SOLVED ASUS M5A99X EVO strange cpu voltage

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fema90

New Member
Joined
Mar 6, 2013
Hello!

I tried to find an answer but couldn't, so please forgive me if this has been asked before.

I have an ASUS M5A99X EVO and an FX-8120 and I'd like to overclock. (Well, it is already overclocked...)
Everything is fine, I can reach very nice clock rates, but there is one thing that drives me crazy. No matter what I set as CPU voltage, it just keeps changing it. For example, I set ~1.37, it became ~1.39, which is quite hot and I don't want to run it hot (I'd rather reduce the clock rate), setting it 2 steps lower (- button), instead of ~1.36 it became 1.34 (which is too low and thus unstable).

What function should I disable or set another way? CnQ and Turbo core are the things I read somewhere but I have them turned off from the moment I started to OC. I thought it's something with the LLC, but that behaves even more strange. At the moment it is the 2nd highest, because the highest set insane CPU voltages and the 2nd was the closest to what I set.

Any help is appreciated.
Thanks.
 
Also, disable C1E and C6 and APM. But please realize that what you set it to in bios and then what its reported by Windows software are seldom going to be exactly the same. By the time you boot into Windows, not only are you dealing with the accuracy of software reporting issues but also load variations. I have a hard time imagining though, that 1.39v is going to be a lot hotter than 1.37v. You are only talking about .02 volts difference.

LLC is another variable. Load Line Calibration. And with it there is a wide range of how it is implemented in different bioses. Originally, it was designed to offset the natural drop in voltage as you transition from bios settings to loading when running Widows applications (vdroop) but it is often implemented to shore up the voltage at idle in Windows as well (vdrop).
 
Thank you for the answer.

The functions you mentioned above are already disabled. As you may have guessed, I'm not that much of an overclocker, I mostly just follow guides. That was the first time I had an issue with the voltage difference. I wanted to set 1.45V, but as soon as Prime95 started, it got raised automatically to almost 1.5V and the PC shut down.

You mentioned that Windows may report the value wrong, but BIOS says the same. CPU voltage is set to 1.386750V, but right next to it (and even in the H/W monitor part there) says it's 1.356V.

Sadly, I don't know much about vdrop and vdroop, I don't even know if they matter now or not. (In the past I had a 955BE OC'd and a 2500K OC'd and didn't come across these.)

Again, thank you. :)
 
1) 4.2GHz, but no matter what I set, the difference is there.

2) LLC is set to the 2nd highest.
 
If you set the LLC to regular/medium, your volts won't jump like that under load. The higher you set the LLC the higher the voltage offset at load. My board on the extreme setting will jump 0.7 volts.
So if you drop the LLC setting you may need to increase your V-core voltage to maintain stability but what you set in BIOS is what you'll see in HWmonitor and it won't go up under a load.
 
Oh, I see. Thank you. :)

If I may ask one more question, can you please tell me what is the preferred method? Higher LLC with lower voltage (that way idle states should be cooler, right?) or lower LLC with higher voltage?
 
fema90, you may want to have a read of the latter part of this post there is some interesting things about LLC and Cpu V core in it.
 
fema90, you may want to have a read of the latter part of this post there is some interesting things about LLC and Cpu V core in it.

Forgive me, but I can't figure out what post you are talking about. :-/
And by the way, I welcome every suggestion on what to read. :)
 
Not sure if this is the post Mandrke was referring to but
http://www.overclockers.com/forums/showthread.php?t=728247&page=2
I think for now fema90 If I were you I'd leave it the way you have it and work from there cause you already have a pretty good idea of the amount of increase you are going to get to the V-core. Once you have your OC established then maybe take the time to test the different LLC settings and see what suits you. :thup:
 
Thank you both for the answer, that was a good read. :)

Now it's much more clear.
 
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