strange power problem

[Decus]

Hi, I'm experiencing some odd behaviours with my PC powering up and and down:

Powering up
The computer needs to beed turned off completely from the switch at the rear. When turned on again from this switch, no matter how long after the system was shut down, the fans automatically come on (system fan and cpu fan) and the hard drive spins. This never happened before, only by pressing the switch on the front of the case would power-up these devices.

When the switch at the front of the tower case is pressed nothing happens. I have to hold it down for 5 secs until all lights go out, switch the power off from the rear again, switch it back on and immediately push the power switch on the front of the case again.

Once the power LEDs light, everything else works fine (though PC seems a bit slow but not sure if problem is related)

Powering down
If I shut down the computer from Windows (Windows 2000 pro)
the PC shuts down completely. But then about 5 minutes later the system will turn itself back on again - fans going and HDs spinning - bizarre! That's why I need to turn the switch off at the back to have COMPLETE shut down.

I thought it might have been my motherboard playing up so I changed the MB and stripped everything else out - but still having the same problem. To be honest, powering up is a whole lot easier now than with the last MB, before I had to turn the switch on at the back and then wait at least 5 mins before trying the switch at the front!

I have a an ATX power box, ASUS P4PE-X/TE MB, 2 HDs, 1.5 GB Pentium processor.

 

[DragonQ0105]

Try another PSU - prefereably higher rated (e.g. If your Power Supply Unit is a 250W Unit, get hold of a 300W or 350W Unit and try it). Although both PSUs have to be of the same format, it's not a problem because almost all PSUs are ATX Format.

 

[kjv1611]

What are your other system specs? If you have a high-end video card such as radeon 9800 or nvidea 5900, then it'd be adviseable to get at least 400 Watt PSU. Also, if you get a cheap/generic PSU, then you may get a good one, or you may not. I recently blew a Skyhawk 400Watt PSU, and went ahead and dished out the cash for ah Thermaltake 560 Watt, I believe it is. It's right close to $100, but it is very quiet, runs cool for a PSU, and definitely not going to overload it. Just some advice on what to buy, but it definitely sounds like you need a new power supply. Mine was similar - I opened it up and looked, found that one of the resistors or whatever had literally popped off! (the Skyhawk one) From what I've read, though, don't go opening a PSU unit like I did unless you are very very careful, and have some knowledge of electronics. The key word is CAREFUL!

Stephen
"Jesus saith unto him, I am the way, the truth, and the life:
no man cometh unto the Father, but by me." John 14:6 KJV