[SOLVED] First time undervolting a cpu, was hoping for some guidance

Arbiter051

Distinguished
Mar 28, 2016
375
4
18,795
9900kf
Noctua my-d15 cooler
Gigabyte z390 Aorus pro
32gb Corsair lpx (I think that is the name) @3000mhz
Corsair rmx 850w gold 80+ psu

I decided to try and undervolt my cpu but I have a few questions just to make sure I did it correctly.

The only things I did was I set the core multiplier to 4.7 and I set the voltage at a manual setting. I touched nothing else.

At first I tried setting the voltage to 1.2 (which is the default if I remember correctly) and Aida 64 froze instantly. I noticed that I was getting a lot of vdroop because I was going down to almost 1.000 volts. I haven’t touched LLC and have enhanced core ratio disabled in my bios. I did try overwatch before a stability test and I was able to play a quick game at 205fps with my settings all at the lowest without any issues. I even saw my temps drop more than 10c from what they usually are at.

I then tried 1.23 and Aida 64 ran, but it said there was an error and stopped the test in 2 minutes.

Right now I have it at 1.25v and 34 minutes in as I write this. No crashes, max temp is 67 on 2 cores and package. I haven’t tried prime 95 yet. My voltages in hwinfo64 are around 1.01 to 1.113 in the vr vout sensor and for Vcore it says 1.128 to 1.058 at the peak.

Is touching only the core ratio and voltage an ok thing to do?

Will I damage anything by doing what I have done? (Yes I know over voltage is what kills, but I just want to be sure)

How long should I run Aida 64 and prime95 for?

Are these voltages ok?

Thank you.
 
Solution
You really think so? I’ll have to try that then. Maybe 4.8, would feel good haha.

How long should I run Aida and prime95 for? I’m almost an hour in atm and everything seems stable
I don't use aida personally. I run memtest86 with only XMP enabled before I do anything. I then use Intel Burn test on it's default test as a quick proof of concept while tweaking settings. I then run P95 26.6 small FFT for an hour keeping an eye out to see if workers are crashing. After that I run realbench for 8 hours. This has worked great for my sytems but YMMV.

Gigabyte actually has a decent guide for OC'ing a 9900k:

https://www.gigabyte.com/FileUpload/Global/multimedia/2/file/525/946.pdf

Darkbreeze also put together a good general OC...

rigg42

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Oct 17, 2018
639
233
2,390
Over voltage isn't what kills. Over current and heat is what kills. You would be safe at 1.35 - 1.4 volts if you could cool it. No worries there. Run the LLC at whatever the step below turbo is. You could probably run it at turbo as well but shouldn't need it. You should be stable closer 1.2 with some LLC. You'll save some power consumption and heat at idle that way. You also might be able to squeeze out some more clock speed.
 

Arbiter051

Distinguished
Mar 28, 2016
375
4
18,795
Over voltage isn't what kills. Over current and heat is what kills. You would be safe at 1.35 - 1.4 volts if you could cool it. No worries there. Run the LLC at whatever the step below turbo is. You could probably run it at turbo as well but shouldn't need it. You should be stable closer 1.2 with some LLC. You'll save some power consumption and heat at idle that way. You also might be able to squeeze out some more clock speed.

You really think so? I’ll have to try that then. Maybe 4.8, would feel good haha.

How long should I run Aida and prime95 for? I’m almost an hour in atm and everything seems stable
 

rigg42

Respectable
Oct 17, 2018
639
233
2,390
You really think so? I’ll have to try that then. Maybe 4.8, would feel good haha.

How long should I run Aida and prime95 for? I’m almost an hour in atm and everything seems stable
I don't use aida personally. I run memtest86 with only XMP enabled before I do anything. I then use Intel Burn test on it's default test as a quick proof of concept while tweaking settings. I then run P95 26.6 small FFT for an hour keeping an eye out to see if workers are crashing. After that I run realbench for 8 hours. This has worked great for my sytems but YMMV.

Gigabyte actually has a decent guide for OC'ing a 9900k:

https://www.gigabyte.com/FileUpload/Global/multimedia/2/file/525/946.pdf

Darkbreeze also put together a good general OC guide here on the forums:

https://www.gigabyte.com/FileUpload/Global/multimedia/2/file/525/946.pdf

CompuTronix also put together a must read sticky for Intel users:

https://forums.tomshardware.com/threads/intel-temperature-guide.1488337/
 
Solution