Mosfet Burn

[Darsh]

Hi, I have quite a big issue, we were "upgrading" my motherboard Rampage III Gene to liquid cooling and a friend of mine start the motherboard without the heat sinkS and as a result he literally burn the last Mosfet of the VRM. As far as I can tell, the only thing burn is that last Mosfet from the top of the line. Now, I would like to replace it, but I don't want to end up buying the wrong replacement. The Mosfet mothel is 9025L but the number under the mothel change in the electronic stores that I've seen on line, some say PH instead of PBm. So, any thoughts? advices? I would really really fix my old Gene, I love that motherboard

[cl-scott]

The problem that comes to my mind, is that the damage may extend beyond that specific chip and into the circuit pathways leading to/from the chip. I'd really suggest trying to find someone trustworthy in your area who's equipped to do a pretty detailed diagnosis of the damage to the board. It may well be that there's some damage that extends beyond just that chip, and it's not really possible to repair the board.

[HiVizMan]

Starting a motherboard without any cooler on the CPU will not cause your mosfet to burn out. I have demonstrated this a number of times to students at events. All that I have ever had happen is that once the temperature gets to the cut off point the system shuts down and will not POST until the heat has dissipated. I wonder if something else caused that short to happen? If that is the case make sure that you have fully inspected the area's affected to see that whatever the cause may have been it is no longer present.

http://www.nxp.com/documents/data_sheet/PH9025L.pdf

Pretty sure this is what you are looking for.

[Darsh]

HiVizMan wrote:
Starting a motherboard without any cooler on the CPU will not cause your mosfet to burn out. I have demonstrated this a number of times to students at events. All that I have ever had happen is that once the temperature gets to the cut off point the system shuts down and will not POST until the heat has dissipated. I wonder if something else caused that short to happen? If that is the case make sure that you have fully inspected the area's affected to see that whatever the cause may have been it is no longer present.

http://www.nxp.com/documents/data_sheet/PH9025L.pdf

Pretty sure this is what you are looking for.

Mmm, look, all I remember is that I have all the heat sinks removed, the one that covers the Mosfets area and the NB, plus the heat sink of the CPU (WITH the cpu still put), I was doing something, can'r recall what, but I was there working in the motherboard with him, and suddenly out of the corner of my eyes I saw him plugin the 24 pin and the 8 pin into the motherboard (I have no idea WHY) and a dense white and smelly smoke came out of the last mosfet and it was... "reshaped" like with a little bubble above. I assembly the motherboard to original specs and it starts... once, I run Prime64 and it seams to work ok, but then I turned of to see if it could start again but it never did. I have a friend in USA who's going to send me a replacement (if it exist) but I needed to be sure I'm buying the right one. So, here's my question (sorry for the silly of it) but that PH9025L is the same one? I mean, the one that I have says PBm and this is PH... I already bought a R3F but I want to try Weld (?) that mosfet. Any how... THANKS for the reply (and sorry for my English)

[HiVizMan]

No problem my friend, I hope you get it sorted. I know what it is like to become attached to a motherboard. I have one board that would break my heart if it died.

Please do keep us informed how the 'fix' works out please.