New Power supply?

fixing a friends computer and it turns on sometimes and when you turn off and do something like install more ram or turn it off sometimes it doesn't turn back on until next day so i believe its the power supply and need a 400watt but looking for the Dimensions : 5.8" X 3.25" X 4" (WxHxD) for Compaq Presario 061 S5314ST. on the manufactures website its like $64 to buy one but ain't going to spend that money unless it is the power supply. main connecter is 20 pin and CPU is 4 pin.

question is on newegg when it says 20+4 pin is the 4 pin attached to the 20 pin or not attached?

 

Since it starts sometimes, I would replace the CMOS battery before going for the power supply. With some computers a bad CMOS battery can cause problems. That it has trouble starting after being unplugged, points to the battery likely being bad.

 

Hmmm, I have never seen that. A bad battery, in my experience will not stop the computer from at least starting the POST - where it may encounter a checksum error due to changed settings (due to a weak battery not holding the date/time and drive data).

Still, a battery is only a couple dollars, so little is lost if not the problem.

Ummm, it's a HP/Compaq.

As for 20/24 pins, all new PSUs will come with 24 pin connectors, but every one I have seen, the last 4-pin part can be broken away, and connected (or left unconnected) as your motherboard requires.