Need tips on undervolting Athlon II X4 630

doveman · Post by **doveman** » Thu Jun 24, 2010 2:52 pm

I'm currently using K10stat and it's set to:
1.4v @2.8Ghz
1.3v @2.1Ghz
1.2v @1.6Ghz
1.1v @800Mhz

I'm sure the voltages can be dropped somewhat but I've got no idea where to start so I'm hoping someone's got some experience with this CPU or at least knows enough about it to suggest what I might be able to drop the voltages to.

As this is my HTPC, it doesn't get stressed much and even when running Mediaportal, it seems to stay at 800Mhz. I was even watching an HD mkv last night and the CPU stayed below 10%, so the onboard HD3300 must have been doing most of the work

Vicotnik · Post by **Vicotnik** » Thu Jun 24, 2010 5:05 pm

You can probably go much lower at 800MHz. Try 0.8v or less even.

doveman · Post by **doveman** » Thu Jun 24, 2010 5:17 pm

Thanks.

Any suggestions for the other end? I imagine it can manage just fine on lower than 1.4v, I'm just not sure how much lower.

snaky_2004 · Post by **snaky_2004** » Sat Jun 26, 2010 2:15 pm

Hy,
I own an athlon II x4 635 and i undervolted my cpu from bios to max 1.25V, and it is stable. In idle it drops tu 800 mhz and 0.9 V.

andresgriego · Post by **andresgriego** » Mon Jul 05, 2010 3:22 pm

You need to use trail and error to determine the lowest voltage a cpu can do for a particular MHz. I like using Hyperpi to load the cores, run the 32M test and let her go. You should get a bluescreen or crash pretty quickly if you've pushed the cpu beyond what it can do.

While not the same cpu, I have a quad-core deneb (unlocked Athlon X2 5000+) that has the voltage set to 1V with a max speed of 2.2GHz .... stable as pie.

nwbdan · Post by **nwbdan** » Tue Jul 20, 2010 10:21 am

I'm currently on my Phenom II X2 550 BE unlocked to 3 cores and doing 800Mhz @ 0.7375 VCore and 1.175NBv (this last one because I'm using 1600Mhz RAM). And this is how low I've tested it stable so far, I'm hoping it can go down further.
So you should have lots of room for undervolting that 800Mhz P-State.
The only real way of doing it properly is really trial and error. I usually drop one setting of vcore at a time and then test it for 3h using Prime 95 (Small FFT if you dropped Vcore, Blend if you dropped NBv). Once that passes I move on to the next one.

As you seem to have noticed 800Mhz is probably the most important P-State as the CPU tends to stay there a lot, thus turning it into the one that's going to save more power/lower temps if undervolted.

Actually, the one thing I'm not sure I have optimized are the % at which it trottles up or down between P-States. What are yours?