Power supply low voltage 5V rail.

[Xenos]

My ULTRA 800W power supply has failed and on my ultra power supply checker I have lost the PG signal. The checker shows all cable plug voltages good though. However on checking with a multimeter I have observed that all of the 5V outputs have dropped to 3.8V. This I think is where my problem lies. Does anyone have any experience in locating and correcting this problem?

 

[rolli59]

Replace it with a quality unit. It is not worth the effort to try to fix it.

 

[Xenos]

Thanks partner, but have already done that. Was not thinking of reusing it in a computer; really want to convert the thing to a homemade lab bench top power supply. I however need to have the 5V working as well as the other voltages. Thus the reason why I wanted to correct that problem before proceeding.

 

[rolli59]

Maybe this will help understanding what is involved http://www.pavouk.org/hw/en_atxps.html.

 

[Torn Mind]

Probably need to learn soldering to put new caps or MOSFETS on.

 

[Xenos]

Thanks rolli59. Have been perusing the schematic. Could be a number of things but am leaning toward the IC3 regulator. Will have a look when I get off from work.
And thanks torn mind. Did not notice any swollen or apparently defective caps but will do a more thorough inspection later. Will identify and replace that 5V regulator and see what happens first. Thanks guys.