Reparing a PC power supply

[menkelis]

Just asking to confirm something, I am just a newbie at this.

I have a 300w PC power supply that is taking about 2 minutes to turn on.
So I took it apart and the first thing that jumps out at me is a big
capacitor that has a bulging top, that is sitting right next to a big heat sink.
I have removed the cap and it is marked 2200uF@16vdc.
My fluke 87V says that the cap is 900uF, so just to confirm what I am seeing
the cap is BAD and should be replaced.

[mariush]

Yes. It should be replaced.  But keep in mind that if that one is bad, so could the others be in various degrees of "bad", even though they're not swollen.

[electronics man]

What is the temp rating on the cap as if it is next to a heatsink and it is a low temp one (105c) then obviously that is bad design.

[menkelis]

The cap that is in question is rated 105c.

I was able to briefly get the power supply to start up in about 6 seconds, which is a lot better than waiting two minutes
but then it stopped again.

With the high density of this SFX power supply and my not so perfect eye sight I thing that I will
just opt to replace it with a new one instead of trying to hunt down everything.

[mariush]

You should also have a look at the 5v Standby capacitor (it should be one rated for 6.3v-10v closer to the heatsinks) and should also look for some smaller capacitors, something like 10-47uF 35-100v which may also be dried out a bit and therefore taking a longer time to indicate "power good" to the computer.