Start up problem

[ddchrist767]

i have a pentium 4 ibms motherboard, p4 1.7gb processor. all connections are complete and correct to the best of my limited knowledge. the atx power supply (400watt) appears to be powering the board, there is a red led which is lit and the keyboard lights up.
When power is on the fans will not run including the power supply and cpu fan. any troubleshooting advice would be appreciated.

 

[RealBlackStuff]

Did you freshly build that computer?
If so try to re-seat the memory and all cards. Did you connect the P4 special cable from PSU to CPU/mobo?

If it was running before:
Try re-seating memory and all cards.
If you have another PSU from another computer, try that first (if it is P4 campatible).
You may have a faulty PSU. If no fuse accessible from outside, look for a fuse inside the power-supply and replace that if it is broken (normally small glass tube with thin wire, about 1 1/2 cm long). Be extremely careful not to touch any capacitors and open wiring inside the PSU.

 

[Spike]

Just thought I'd add;

Aside from the fuse, there is nothing in a power supply that can be checked/changed easily. Given the High voltages that PSU's can be capable of producing, be very careful as stated above. If it is not the fuse, and you still want to troubleshoot the power supply, there are only two ways to really be considered.

1, Use an approved electrical tester/multimeter to check whether the voltages for each cable are correct and within tolerance. If not, get a new power supply. Always test from the P9 plug end of the cables.

2, Buy a new power supply and try it. They're cheap enough these days for you to buy one of the cheaper ones as a test unit.

Also, if you built the system yourself, and it all the connections and card seatings check out ok, depending on what/how many devices you have, try unplugging a few, just to check that you have a sufficient supply.