Tracing the failure source on a mosfet RJK0389DPA (Motherboard repair)

[Stonent]

I have an HP Elite 8300 motherboard that I purchased off of ebay that worked great for all of about 10 minutes and then released the magic smoke on a MOSFET (RJK0389DPA). The board was on an insulated surface with a known good power supply.
It's past the return point because I ordered it before several other parts that I ordered much later before I could test it.

I want to hopefully determine which direction from the chip to look where there could be a problem.  There are no schematics for this board so I'm working blind in that respect

Right now the board powers up and I see the BIOS text for about 3 seconds and then the board powers down.

Here is the datasheet: https://4donline.ihs.com/images/VipMasterIC/IC/RNCC/RNCCS17891/RNCCS17891-1.pdf?hkey=EF798316E3902B6ED9A73243A3159BB0

The Magic Smoke hole appeared between Pin 4 and 9.

Based on the design with the two internal MOSFETs are they trying to spread the load or something else?

I've attached a picture of the board (not my exact board but an identical one)

All 12 MOSFETs in the top right corner are identical.  I'm guessing they are lined up with the inductors that they are feeding into it and then the CPU.

http://imgur.com/a/OJxTs

[Rasz]

first remove that fried part

booting for 3 seconds means there is a very good chance its easily fixable. It might even start working fine after removing this mosfet alone(obviously at a cost of bigger load on the rest, should be a problem with weak cpu like pentiums), or bios enables power saving modes and disables half the CPU power rails (standard on never intel platforms). There are bioses that let you control for that (all ASROCK for example), but hthis is HP so no options for you.