CPU speed rises and falls - why?

somebodyelse · 17 Apr 2014 at 23:58

I have an ASUS M4A78LT-M LE Mobo, and a Sempron 140 CPU. I have unlocked the extra core, but notice that even before I try overclocking the cpu, the multiplier and voltage seems to drop and then climb back up, without any reason. I noticed this happening before I added the program Cool & Easy, which I have now uninstalled again.
Does the mobo have automatic throttling for power saving or is it perhaps a voltage instability I'm seeing? This is happening while the pc has no programs running except wifi and AVG.

ukbilleh · 18 Apr 2014 at 00:01

not sure exactly what is going on here but a long time ago had the same issue on a n amd board randomly blue screening when doing anything intensive.

Try finding the stock safe voltage for the cpu and seeing if you can lock it out in the bios and see if this helps.
Also check for any bios updates which might plug the issue if it maybe a software problem

smogsy · 18 Apr 2014 at 11:19

what is your windows power setting at?

if its on balanced chances are its a power saving feature

Jumper118 · 18 Apr 2014 at 17:22

the second core might be unstable. i would turn off all power saving feature and give it a bit more voltage.

somebodyelse · 18 Apr 2014 at 22:51

Just to say, it seems to have resolved itself. I've fitted a new monster cpu heatsink and fan, and now the voltages are stable, the cpu isn't hunting, and its been running Prime 95 at 100% CPU Utilisation for maybe six hours now. Both cores in use, max multiplier and as far as I can see rock solid. Thanks for your interest and comments, which were generous of you. Just wish I knew for sure what teh problem had been, but if it's gone, then I'm happy! Thanks again.

Jumper118 · 18 Apr 2014 at 23:21

somebodyelse said:
Just to say, it seems to have resolved itself. I've fitted a new monster cpu heatsink and fan, and now the voltages are stable, the cpu isn't hunting, and its been running Prime 95 at 100% CPU Utilisation for maybe six hours now. Both cores in use, max multiplier and as far as I can see rock solid. Thanks for your interest and comments, which were generous of you. Just wish I knew for sure what teh problem had been, but if it's gone, then I'm happy! Thanks again.

good to hear its working. what cooler have you got on it? i had a thermalright hr-02 on my sempron for a bit