OT: PC power supply

[Gib Bogle]

This morning something odd happened with my PC (Asus Core i7 m/b). I started smelling that hot electrics smell, and discovered that the power supply case was very hot. I opened it up (yes, I know) and saw that the two power transistor heatsinks were very hot. Nothing on the m/b seemed to be hot. I put it back together again and now it's running cool as usual. In my experience such things don't just go away, so I expect this problem to recur. I've considered replacing the power supply, but I'm reluctant to do that while the problem might lie elsewhere.

[The Natural Philosopher]

fan clogged?

[Graham.]

Yes, you know, what exactly? Remember this is a DIY group, the "no serviceable parts" ethic and even warranties count for little here.

The last PC power supply I encountered that had a smell of burning insulation but continued to work (for a while) eventually packed up. On examination the main torroidal transformer which was smaller than I would have expected, had crisped up nicely.

Check for discolouration on the PCB that might indicate a dry joint.

[Gib Bogle]

The problem has recurred this morning. The hot smell is the giveaway sign. This time I ascertained that the fan was not spinning. I gave a push, and it started. When I stop it, it doesn't restart unless I nudge it. Apparently a fan problem. That's not so bad - I should be able to buy a replacement. The fan was rather dusty when I first took the PSU apart, so I guess there's dust in the bearings. It really is a bad idea to skimp on the bearings in a component like this - I suppose you get what you pay for though.

[Gib Bogle]

I replaced the fan. It cost a good fraction of what a new PSU would have cost, but at least I know that the fan will not crap out on this one. It's very quiet too.