PSU Repair - Component identification

[bcarm17]

I can't seem to find the exact part I need. The component in question has the markings S43 P17 on it, three legs on one side and what looks to be a mounting tab on the other side. I would love it if someone could point me in the right direction.

[Kjelt]

NXP/Philips PBSS4350X ?
see datasheet, double check though

[bcarm17]

Ok, that's the data sheet I found too but I couldn't figure out what the P17 meant?

[Kjelt]

That's not specified, could be the batch number for quality tracibility or whatever.
Desolder it and measure if it is the specified transistor layout (if it is broken you can test it partly) and if the pcb traces (reverse engineer the schematic) makes sense for this npn transistor, if so order one from some distributor and check if it is about the same.

[bcarm17]

Might just order one anyway and throw caution to the wind. From what I've been able to deduce, that component makes sense. But my electronics knowledge is limited at best. Thank you very much for the help. I'll keep you posted about my success or failure at repairing this psu (Thermaltake 875w)

[TheMG]

I'll keep you posted about my success or failure at repairing this psu (Thermaltake 875w)

Have fun! Just make sure you're wearing safety glasses if you attempt to power up the PSU with the case open. I'm telling you from experience that computer power supplies in general can go off with quite a bang if something isn't quite right. Transistors can end up with big blowholes in them and throw hot shrapnel around.