Try to reverse engineer the area around the transistor, it should be a general purpose 2N3906 or 2N 3904 (PNP or NPN).

Depending on how the transistor is connected to the power rails/if the base is pull up or down, you should be able to identify the type needed.

computerguy08 wrote on 2021-02-05, 11:37:

Try to reverse engineer the area around the transistor, it should be a general purpose 2N3906 or 2N 3904 (PNP or NPN).

Depending on how the transistor is connected to the power rails/if the base is pull up or down, you should be able to identify the type needed.

Good idea!
Looks like it is MMBT3904 (2N3904 but in SOT-23) 'cause its emitter is tied to the ground.

MS-4138 VER: 1.1

Hope this helps.

Hello, I have the same motherboard and it has a socket for a battery, like CR2032. My question is: how many batteries it need, one or two? With only one battery the upper contact (+) does not touch the battery.
The motherboard does not run. it stops in C2C3 codes in the test card. Maybe it needs the battery to star to work.
I have remove the SIMMs modules and the graphic card and it stops in the same point.
It looks like the processor starts but something stops it.
Thank you very much.

Added: I have checked the +5V and 33Mhz in the socket and both are present.
The 32khz oscillator is working

Added: I have checked with another processor 80486DX2-66, instead of 80846DX-33, and the it stops in D3D2.

Added: Two broken tracks. After difficult repair (36 awg wire) without a microscope, motherboard is working but mi question remains, one or two batteries. Thank you.