Computer Randomly Shuts down - possible PSU issue?

[SamuraiSlayer98]

I have been having issues with a dell optiplex 780 that I've modded to work as a media center and gaming PC. The computer shuts off seemingly at random. The event log in windows says the shutdowns are being requested by the button/lid. I read somewhere online that this can sometimes be linked to a PSU. I opened the psu and found a couple bulged caps. Is it safe to assume the psu is dying?

[Cogburn]

I'd say so if those capactiors are bulging. They'll start seeping the electrolytic fluid soon. Id replace it. Have you tested the voltages with a tester? 4/8 pin and 24 pin at least? 

[SamuraiSlayer98]

2 hours ago, Cogburn said:

I'd say so if those capactiors are bulging. They'll start seeping the electrolytic fluid soon. Id replace it. Have you tested the voltages with a tester? 4/8 pin and 24 pin at least? 

I don't have a power supply tester and the psu is a dell proprietary pinout to match the dell motherboard. I don't wanna throw the PC out but the proprietary hardware makes it hard to salvage...