£1.20 MSI DKA790GX Platinum Short circuit issues

[Ashley98]

Hey guys, I'm at it again on the eBay this time with a £1.20 MSI board that caught my eye....descriptions says it doesn't post in which it doesn't when I tested it today.

pressing the power button on the on board switch I hear the PSU shutting down due to short circuit protection 

after fiddling around with the board for 10 mins I got it to boot when I removed the 4 pin cpu power connector 

so I inspected the VRMS and eveything looked fine then a cracked transistor caught my eye under the cpu socket 
transistors reads T04 93 SMD transistor , not sure there is a temporary way to get the board to fire up until I get the replacement part. Unsure which part too ? There is lots of transistors out there and that only what was really on top of the one I pulled off and the one next to the broken one 

would be great if I got the board up and running it looks like new....no dust...heatsinks had there plastic protection covers on too...looks like someone stuffed the cooler mounting up as there was no cpu bracket included.

[ozz]

macsbeach (pete) is the one you wanna talk to about that, im sure hell chime in and tell you how and what,  soon enough

[Macsbeach98]

A picture of this board showing the dead transistor or where it was would be nice.
The only thing a couple of searches bring up about T04 93 is a sot23 NPN multi purpose transistor but the transistor shown is not a 93 but a lot of those transistors are exactly that.
Other than that I havent got much more help I am afraid.

[Ashley98]

Here's a pic of where the component is missing from the 2 next to it are identical 

ibb.co/x8gW6CH

[Macsbeach98]

I would say that is a NPN signal transistor you could probably rob one off another dead board.

One thing the 4 pin CPU power plug only supplies power to the CPU vrm that board has 4+1 CPU Power in the pic below I have circled the three power regulation sets the blue set is the CPU VRM 4 phases for CPU 1 Phase for CPUNB.
The green circled area supplies power to the chipset and probably PCIe power there looks to be a linear regulator there as well as a PWM and is probably what the dead transistor is used as a switch by the bios to change the voltage.
The yellow set is for the memory.

It does seem odd that pulling the CPU power plug allows the thing to turn on I would say there could be a short in the VRM for the CPU as well just because Mosfets look good dont mean one is not shorted.

Anyway replace that transistor and see how you go.
I wold like to know how you go with it.

[Ashley98]

Makes sense now thank you 😉 , I had the heatisnks off when testing the board and both SB and NB were cold. I've got a couple of dead boards just need to order some more solder. Hopefully that is the issue

[eidairman1]

Jan 6, 2019 7:22:13 GMT -5 Ashley98 said:

Makes sense now thank you 😉 , I had the heatisnks off when testing the board and both SB and NB were cold. I've got a couple of dead boards just need to order some more solder. Hopefully that is the issue

Good to know, I was gonna say look at AM2/+ and Am3/+ Motherboards.

I wonder if you could just order those xistors anyway

[george]

How did it go with the board repair? From the picture you posted it seems the missing component was just at the location adjacent to the CPU heatsink clip, component might have been knocked off during locking or unlocking the heat sink to the bracket.