Pc not booting

[Tinker]

I'm trying to fix my brother's Compaq 5000 series. Mobo is a Fic Az31 (Uwave Oem), 700Mhz Duron. When pc is first turned on, the fans and power light run for an instant and then shut off. Or nothing happens at all until front power switch is pressed - then same thing happens. Never gets to Post.

I've replaced the power supply (new Enermax), checked that all sockets were secured to mobo, tried running with just mobo and PS connected, and cleared CMOS. No change.

I've studied Compaq's support files on the subject. Seems to be a common problem, but no tangible solutions for the do-it-yourselfer. Brother bought the pc new several years back and it worked fine until the warranty ran out. Any suggestions on narrowing down the root of the problem? I'm guessing it's a bad mobo or cpu but no idea how to tell which.

 

[Flyboy]

Easiest way to diagnose a bad CPU is to simply swap it out with a different one. Do you know anyone else with a Duron or even an Athlon processor?

I would also swap out the memory too. YOu should easily be able to borrow one or use one of your own to at least rule it out.

Now a motherboard problem can be very difficult (of course). I would try swapping the memory first (because its so easy), then try the CPU if possible. If both still produce the same problem, then your 99% sure its the motherboard. Actually, make sure you remove all unnecessary hardware too- like sound, NIC, etc... If the problem disappears after removing the PCI cards, then try adding one back in at a time to determine which is the culprit.

 

[Tinker]

Thanks for the suggestions.