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Josh-D. S. Davis

Xaminmo / Omnimax / Max Omni / Mad Scientist / Midnight Shadow / Radiation Master

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Tech Support
Josh 201604 KWP
joshdavis
Here's what I sent to Asus.

During troubleshoot of a bad CPU, I accidentally put a DIMM in backwards.
power MOSFET "9915H 345056" overheated, cracked, ruptired, and emitted smoke. This of course voids the warranty of this brand new board.
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Amazingly enough, the second mosfet happens to provide enough power for low-speed, such as accessing the bios. All voltage specs are OK. Once the CPU is cranked up to full speed, the system fails to boot (assuming not quite enough power, or maybe power quality is bad).
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So, since I can't RMA this board, I thought I would replace the mosfet and see if the board still worked otherwise (except the cooked pin in dimm slot 1).
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All online references to this part show that Asus uses it, and that it is TO-252 form factor, and that it is a MOSFET. I couldn't find much in the way of reference to the specs of this mosfet. Could you check with your engineers and see what the specs are, who makes it, compatable part number cross reference, etc?
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Thank you for your time.

Anyone have a clue on where I can find specs for this MOSFET? (9915H on Asus board, TO-252)
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Got a photo of it, perchance? 9915H could be one of half a dozen different manufacturers. :-/

MOSFET, Jenga Fet's Dad?

*nod* I found a 9150H from another MFR which is a 23A MOSFET.

I'll see if I can get a good photo of it. The numbers are etched instead of printed, so contrast isn't very good.

Until then, the general design is:

   ________
  +---------+
  |  9915H  |
  |     (/|)|
  |  345056 |
  +---------+
   |   |   |
   |       |


The top is the back contact. It's not very big and is soldered to a large pad on the top layer of the board.
The source and drain are connected to 2 other pads. There is an identical one right next to it, a pretty beefy cap (didn't get rating, but it looks maybe 2kuf or more) and an LM234 nearby.

This provides current for CPU and DIMMs.

The pic from Asus is Here but it's not high enough resolution to tell anything. The 2 FETs are north of the IDE connectors, between the CAP and the similar package below them.

I'll just have to see if I can get a pic.

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