Replaced north bridge heat sink. Now no power up. Eh?

[Jayce]

Working on an Optiplex GX280 here. It's an older Pentium 4 box. I replaced the north bridge heat sink because the old one was overheating. I was reluctant to do this because my mentality suggested, if it was fine all this time, why now? The caps look good, however there are 2 caps near the processor with SLIGHT upward cones, however no leakage. I've certainly seen worse caps that work fine, but I still took notice to this.

I put the heat sink on, fire it up, oh wait! Nothing. I take ram out. nothing. Removed everything like hard drives, pci cards, etc. Nothing. If I plug in a PSU tester, it fires right up though, which suggests to me everything is okay.

Think the mobo is fried? The user told me it kept shutting off on him after running for a while. I turned it on and every 20 seconds I physically touched the north bridge heat sink. Sure enough, it got hotter, and hotter, and hotter. It never turned off on me because I shut it off manually since I realized it was the issue. It worked on friday. I replace the north bridge heat sink today, and no dice. I did however notice that there's a case sensor on this to see if the case has been opened or not. I read the instructions to reset this and sure enough, no dice either...

Just trying to get some second opinions here. Think the board is toast?

 

[Thomas]

Chances are due to age and heat a small solder joint separated under the slight flexing of you changing the heat sink. I would suggest stripping down the board and do the oven method. Should get you some more use out of that system if you don't plan on replacing it.

 

[S0ULphIRE]

Sounds like it was dying well before you got it. I wouldn't be surprised if the board was dead at all, certainly sounds like that's the case. No beeps with no memory in especially is usually a good giveaway.

 

[Jayce]

Sounds like it was dying well before you got it. I wouldn't be surprised if the board was dead at all, certainly sounds like that's the case. No beeps with no memory in especially is usually a good giveaway.

That's what I thought too. I guess I was just a little "what the??" when I realized it worked on Friday and today it does not. Anyway, I'm going to see if I have a compatible board in my stash, as I DO have a similar Dell system in my stash that I gutted for other parts. The mobo itself might work. We'll find out...