PC Only Boots Sometimes, Often Powers Off

[MConsoletti]

I have had a Dell Studio XPS for a few years now and over the weekend it started freezing up and rebooting. Then it simply refused to boot up. Have it gutted and breadboarded trying to troubleshoot and have a vexing issue. When I short the power button pins it will sometimes boot up and give the correct beep code for the missing components (RAM, video card, etc.) most of the time however the fans whir for a second and then it shuts off. I have shorted and tested the 24 PIN connector from the power supply and all voltages were correct, though I suppose it could be failing under load. What irks me most is it is really a crapshoot if it boots or not, nothing I am physically doing seems to affect its success rate. Would love any tips before I run out and buy a new mobo or power supply or both.

 

[Outlander_04]

I would try a new psu

 

[dextermat]

I second that, if it doesn't help, might be a problem with mobo

 

[spentshells]

Yes it could be damaged firmware on the mobo .... my son pushed the pwr button on and off for an hour needless to say the mobo is punched out.

 

[MConsoletti]

Probably noob question, any way I can try and isolate if it is a firmware problem? My PSU is less than a year old and the fact that it supplies the correct voltages without any load leads me to think it is less likely the issue. Nobody I know locally has a spare PSU so I would have to buy a new one to test it, so if there are any other diagnostic steps I can take at this point before shelling out cash it would be ideal.

 

[spentshells]

easiest way is to try another PSU and run only onboard video and ram