Unusual Problem with ATX power supply and Linux

[Daniel]

I'm having an unusal problem in linux. I am running RedHat 6.0. When i run linux the fan on my power supply will slow down and speed up, seems ramdomly. It does not do this in windows and in BIOS I have turned off Power supply control by OS. Still doesn't fix this problem. I have a PII 266 and 440LX mother board. Could this be a compatability problem?

Thanks

[kwai]

i'm pretty sure that linux automatically tells the cpu to "slowdown" when its not being used (the halt command that makes cpuidle and waterfall popular for win9x). if that's true, and your ps fan is temperature sensing, your fan could just be responding to the lower temp of your cpu/case when the system is idle.

try leaving the system alone for awhile (hour or so) and see if the fan is mostly off. then run some heavy duty programs and see if the fan is mostly on. of course, you'd need to try and keep the room temp as constant as possible while you're fooling around.