My IBM machine won't turn on

[Da_Banig]

Ok I got this IBM machine when I try to turn on, it turns on for half a sec and then it turns off. It will just keep on trying to do the same thing if I leave it without unpluggin the power. First I thought the PSU was bad, so I changed that but that wasn't the problem. I tried to change RAM as well... could this be the motherboard problem? My assumption is it is but I do not have another motherboard to test it out... anyone had/have similar problem? Thanks

 

[Conumdrum]

Dust? bad fan on CPU?

 

[Da_Banig]

Nope, everything is clean and the fan is working. I even swapped another CPU and tried. same thing

 

[engrpiman]

could your power switch be bad. If you short out the power button connectors on most motherboards the computer will turn on then turn off in 4 sec or less. if you are going to try this also test the reset switch. Sometimes a bad connection to the motherboard can make all the difference.

 

[croc]

Perhaps some more system details might help... IBM model #? Processor ? Memory? PSU?

 

[Da_Banig]

I did another test and I found out something if I took out the CPU and turn on the computer, it looks like it runs fine all the fans turns on and start spinning. It can't be the CPU issue becacuse I put in another working CPU and tried. I am not next to that PC now I believe the model is 8078, P4 3.0Ghz, 512RAM 200PSU

 

[LoneEagle]

Maybe a defective MB. BIOS can't communicate or having problem while testing the CPU?

 

[Da_Banig]

Could be, just don't wanna conclue that yet because it is then the whole PC is usually since I am not going to get another motherboard lol beside its a pretty old PC