Hello,
I am new to this forum and would like to thank you for having me. Now, my question.....I have an older Epox mobo with an AMD 950mHz prosessor. The cpu fan went out and I replaced it with a new fan/heatsink combo, but it will not boot...fans come on for a second, then shut off. I am sure it is the RPM sensor in the bios, but I can't figure a way around it without getting into bios. I have tried fans as high as 4800 rpm and still no luck. Any help would be greatly appreciated. Thanks,

Ken

Are you sure the CPU wasn't damaged when the first fan went out?

Have you tried connecting the fan power directly to a line from the PSU rather than the motherboard?

Thanks for the reply jephree,
I am sure the cpu was not damaged....original fan was making a bearing noise, so I decided to replace it before it went completly out, then I started having the no boot problem, even with original fan, such as it was. If I were to connect to PSU, would be same result cause bios would not see fan rpms. Thanks again,

Ken

This should not cause a no boot.

For example I install liquid coolers a lot.

Hence I get a BIOS error that the CPU fan is not detected.

I simply F1 the error or turn off error stops.

This should really not stop the BIOS POST.

Have you tried clearing the CMOS?

Also check all you connections and reseat the RAM etc.

Thanks jephree,
I will try your suggestions.

Ken