Computer shuts down after 4 - 5 seconds

[Seelie]

I'm working on an old Compac Presario. First I had to hot wire the on switch, now when I plug it in it only works for 4-5 seconds then shuts off. I've already replaced the PSU and checked the RAM, but no change. It has an INTEL CPU, haven't looked close enough to tell speed. Any suggestions?
Thanks,
Seelie

[jbennet]

overheating?

clean out the dust, open all the windows + doors and run it in the middle of an open space

see if it stays on.

[Seelie]

jbennet,
The first thing I did was clean out the dust. I now have both the side cover and the face off. I even tried cleaning off the heat sink compound and putting new compound on the CPU. I'm really thinking that the CPU is bad.
Thanks,
Seelie

[willcomp]

The reason it's shutting off after about 5 seconds is because you "hot wired" the power switch. Power switch is a momentary contact switch. When it stays closed (as in your case), the PC will soft power off after the preset time delay which is usually 4 or 5 seconds.

Disconnect power switch and use a jumper or small screwdriver to short power switch pins on front panel connector.

[techno t]

The reason it's shutting off after about 5 seconds is because you "hot wired" the power switch. Power switch is a momentary contact switch. When it stays closed (as in your case), the PC will soft power off after the preset time delay which is usually 4 or 5 seconds.

Disconnect power switch and use a jumper or small screwdriver to short power switch pins on front panel connector.

yep if its constantly on then it will be like pressing and holding the power button to knock the PC off.

The old screwdriver power on technique will verify if you have a serious problem or not.

*

[sun1234]

power on pc after 4-5 seconds power off