Compaq Evo D510 Convertible Minitower Power Supply Replacement

[Rogueninja12345]

Hello everyone! I have a Compaq Evo D510 Convertible Minitower. I just recently removed the power supply to dust the insides and everything, but now it won't work correctly.

Every time I try to boot it up, it won't work. No lights come up or anything. The only lights that do come up are the three LED lights for the power switch, CR1, CR2, and CR4. Every time I press the power switch, CR2 lights up, letting me know that the power button works.

I've tried switching the wattage from 110 to 220 for the first time and it still didn't work. The only thing that happens where the computer turns on is when I plug in the power cord directly into the power supply. The computer stays on for about a good 3 seconds with every thing running before it shuts down again.

I plan to replace the 277910-001 HP 220 WATT Power Supply I have with another 277910-001 HP 220 WATT Power Supply, or a 277979-001 HP 220 WATT Power Supply Spare Part.

Links to the parts:
https://www.serversupply.com/POWER%20SUPPLY/DESKTOP%20POWER%20SUPPLY/220%20WATT/HP/277910-001.htm
https://www.serversupply.com/POWER%20SUPPLY/DESKTOP%20POWER%20SUPPLY/220%20WATT/HP/277979-001.htm

My questions are:
What's wrong with my computer?
Should I replace the power supply?
Which power supply part should I choose for my Desktop? The original part (277910-001) or the spare part (277979-001)?

Thanks for all your help in advance everyone!

 

[WR2]

I just recently removed the power supply to dust the insides and everything, but now it won't work correctly.

My questions are: What's wrong with my computer?

Have you found a Compaq Evo D510 Convertible Minitower service and repair manual to help troubleshoot the problem?
It might have a remove/replace guide for the PSU that could shed some light on why it's not working now. (like missing a PSU to MB connector).

 

[Rogueninja12345]

I've looked at all the manuals I could find and the only thing that was any help at all was a map of the mother board and where all the power connectors should go.

Here's a link:
http://www.manualshark.org/m/hewlett-packard-compaq-evo-d510-convertible-minitower-compaq-evo-d510-convertible-minitower-personal-computer-illustrated-parts-map-27716/

I know where P1, P2, P3, P4, & P5 go. P1 as the main power supply, P2 to the hard drive, P3 to the processor power supply, P4 into the first DVD Drive, and P5 into the second DVD Drive. Those are all the connectors that fit anywhere. The rest of the connectors can't seem to go anywhere.