Recapped the board but it still wont power up

[ohms]

Hey guys,

I'm new to this whole recapping of motherboards. One of my old boards (MS-6163) died the other day. The computer was on and it all of a sudden shut off by itself. It would no longer power up. So instead of chucking it, I tried to diagnose the problem.

I removed all components except for cpu and ram and tried to power it on. What seemed to happen is that for a split second the LED lights will come on and go off. I noticed the caps were bulging and oozing with a funny smell, so i decided to attempt recapping the board.

I finished soldering the new caps in and now when i attempt to power it up, the same thing happens, I can smell a slight electrical burning smell, coming from the area right in between the caps, its actually the same smell that was orignially eminating from the area. It seems to be either coming from these black things or the coil. There is no sign of anything burnt on the board, so im not sure what is causing the smell.

I know this board isnt worth more than 5 bucks but i would like to fix it. What do you guys think, is there any hope for this board? I have some pics of the area. I hope this works.







Can you tell anything from these pics?

[Topcat]

Check your VRM FET's for shorts. Also, check your PSU.

[ohms]

I know the PSU is good. Ive used in other machines. I dont know what VRM FET's are or how to check for shorts. Can you please explain. Thanks

[willawake]

that is a rather typical way for a 6163 to go. I can help you with half the question, the vrm fets are the 2 black square boxes inbetween the two rows of caps next to the slot 1. they are marked CEB703AL. I have some pics from before, on the first pic they are marked CET.

[sulbert]

Make sure the CPU is still OK.

[ohms]

Can I replace these VRM fets? Is there a chance that many more components are blown? The CPU is still good, I have tested it in another machine.

[kc8adu]

you could also have chipset damage.
sometimes the vrm chip itself dies when a fet shorts.an example is the sc1153csw between the inductor and the paralel port.if you get a blink and the fans twitch you likely have a shorted fet.

[AK0R]

Here is a link to the VRM FET test procedure:

https://www.badcaps.net/forum/showthread.php?t=600

[ohms]

Hey AK0R, thanks for the link. I'm a total newb at this so there are a few things I want to ask.

Of the 20 pins which pin is the load supply pin?
Of the three legs the VRM FET has which one is input and which one is ouput?

[kc8adu]

looking at the fet as it lies on the board with the pins pointed at you they are from left to right g d s.
gate drain source
they usually short d-s

[ohms]

Ok so im assuming the source is the input and the drain is the output. Do you think its even necessary to test the fet if it smells like its burning? From what ive gathered here the chances are pretty high that the fet has shorted. Can i get a replacement fet somewhere?