My 450M PIII Packard Bell stopped the other night - fans & HD stopped, monitor went to standby. Both the power and HD lights stayed on, but with no HD activity. Power button (ATX case, no reset) has no effect at all.
My first thought was some sort of PS failure, so I tried another, and also another switch, but had exactly the same symptoms.
The PS fan runs, but the processor & (I guess) on-board graphics fans are merely "alive".
Swapping the PS will have re-seated all of the power connectors. Next, I'm going to take EVERYTHING off, dust & reassemble.
My question is, should something have failed, what is most probable given these symptoms, BIOS, MOBO or CPU?
Hi swintex. I don't know the Packard Bell PC at all, so I will make some guesses.
You have eliminated the PSU and switch. The BIOS is very unlikely to cause any of the symptoms you have described. It is possible (but unlikely) that the motherboard has a fan speed detector that shuts down the motherboard if the fan is too slow, in which case the cpu fan could be the cause of the problem, or there could be a motherboard or cpu failure that is overloading the PSU (more likely).
When you take everything off for a dusting and reassembly, leave them all disconnected, with just the motherboard, power supply, power switch and fans connected. Do the fans run at normal speed then? If they do, start reassembling bit by bit until things go wrong.