Legit Reviews

I have had my surfing PC hooked up to my new Kill A Watt EZ for a few days now. In the course of that time I went back into the BIOS and enabled AMD's Cool N Quiet to see how it affected the power draw. Typically I keep CnQ disabled because I like having all my MHz when I need them. I don't like relying on a driver/software to tell my CPU to get it's butt in gear.

AMD Phenom X3 8450
CnQ Enabled - Idle 99W
CnQ Disabled - Idle 111W

This isn't a stellar increase in power draw (~10%). Sure this load is measuring the entire system but I still expected it to drop in semi-bright light bulb territory. Am I missing something here?



Hmm... Looking at the CPUID screenshots I think I might have found the problem. When CnQ kicks in isn't it supposed to also lower the CPU's voltage when it drops the multiplier? It seems like when my Athlon 64 (S939) 3000+ and later Opteron 170 would lower the multiplier it would also adjust the VCore accordingly.

That's odd - I have heard good things about the Cool N Quiet feature...

Do you have anything in your BIOS that is set manually, with regards to frequencies or voltages? That could be overriding its capacity to lower its voltage as much as it wants to.

I know on some motherboards for the 1156 chipset (P55) if you enable XMP, that also affects the motherboards ability to bring the power consumption down even if the features are enabled.

Something to consider.

It's all set to Auto in my BIOS. Unfortunately if I bump the FSB just 1 MHz it makes the computer unable to boot. But using Foxconn's software I can software overclock it to 225MHz. Shurgs.

Major_A wrote:It's all set to Auto in my BIOS. Unfortunately if I bump the FSB just 1 MHz it makes the computer unable to boot. But using Foxconn's software I can software overclock it to 225MHz. Shurgs.

ha, i have an athlon xp 2100, it doesn't boot unless it is set as somewhere between a 1500 and 1700 in the board i have. but it has decided to not run at all anymore so it's sitting on a pile of stuff right now

also, I don't ever use power saving features, the difference in wattage at the wall is too marginal for the headache

Guess AMD processors have a mind of their own. Should've named this PC HAL9000 instead of my main rig.