Blown MOSFET..

[Timp74]

Hey, could anyone tell me what one of the MOSFETs does on ASUS X299 motherboards? It's the one marked in the attached photo of a Rampage VI Extreme. Only ASUS x299 motherboards seem to have a MOSFET like this. The Drain pin is connected to Vcore/Vccin and Source to ground I think, although that maybe a fault with the board I'm trying to fix. The MOSFET has blown and I can't work out what it does or if the PCB has a short to ground.

[restsugavan]

I think RMA or Exchange the board is better idea.
If you trying to do it will void the board warranty.

[Timp74]

restsugavan wrote:
I think RMA or Exchange the board is better idea.
If you trying to do it will void the board warranty.

I would if I could but the warranty is already void. 😉

[Timp74]

The more important question for fixing the MB is if the PCB is shorted. Should the source on this MOSFET be connected to GND? If anyone could measure this on a working ASUS x299 board that would be great. The source is the three pins connected together on the left of the 4C06B (NTMFS4C06N) MOSFET in the photo. There is a similar MOSFET on some ASUS X99 boards too, and on some of them this MOSFET hasn't been populated. It is odd..

[Braegnok]

It looks like perhaps the output to the VRM is shorted.

As shown on this Rampage VI Apex board, @ 4:00 min into video. https://www.youtube.com/watch?v=e-4nCAhaR9g

You might have some luck over at Badcaps Forums with what that chip does. https://www.badcaps.net/forum/

And or consider sending your board in for Repair Service to confirm if the PCB does indeed have a short.

[Timp74]

Braegnok wrote:
It looks like perhaps the output to the VRM is shorted.

As shown on this Rampage VI Apex board, @ 4:00 min into video. https://www.youtube.com/watch?v=e-4nCAhaR9g

You might have some luck over at Badcaps Forums with what that chip does. https://www.badcaps.net/forum/

And or consider sending your board in for Repair Service to confirm if the PCB does indeed have a short.

Hey, I posted on an ASUS MB owners forum but haven't had much of a response. I'll give badcaps and go... Thanks.

[Braegnok]

Timp74 wrote:
Hey, I posted on an ASUS MB owners forum but haven't had much of a response. I'll give badcaps and go... Thanks.

Sorry I could not find any information on your motherboard as to exactly what that chip does, but due to it's location near the VRM and CPU, I would be concerned also with a short damaging the CPU.

I have sent a few boards to Badcaps repair service for cap and chip replacement they are a top notch shop, have a lot of smart folks on the forum.

Good luck, hope they can help you.