Power supply question.

[Husky01]

If Im testing to see if a power supply works. Could I just plug the power supply into the wall and should the fan still kick on?

[Kermit de frog]

The motherboard needs to send the signal to the power supply to turn on all the voltage lines.

Whats the problem?

[1701E]

No, a PSU won't power on unless you have it plugged into a source that will turn it on (ex. computer).  No risk of killing the computer if it's a reliable PSU.

[NOT]

you can test it this way, you need to jump two pins on the main connector. do a google search for power supply testing, you should find it pretty easy. now, although this will turn it on, if you don't have a PSU tester, or know your way around a multimeter all you will be sure of is a working fan.


here is a link to an explanation.
http://www.duxcw.com/dcforum/DCForumID3/447.html

and here is another.
http://www.duxcw.com/faq/ps/ps4.htm


NOT

[Husky01]

Whats the problem?

Well my power supply for my computer started going bad Wednesday, so I went ahead called up 5 oclock computers and bought a new 550 watt (I think) power supply. Went in opened up the computer, disconnected the old power supply and plugged in the new one, and it doesn’t work. I know that power is flowing through it because there is a green light on the motherboard that lights up when I flick the power supply on. When I go to turn on the whole computer though it won’t start, no fan noise, no nothing. So I put back in the old power supply to see if I had just bought a bad one. Plugged back in the old one made sure everything was hooked up correctly and nothing same thing power to the mother board but it won’t start up. So my mom is just going to run it up to her tech people at work today and see if they can figure out what is wrong with it. Any ideas what it may be?

[NOT]

does anything at all happen when you push the on button?? if not, could be a bad switch. did you plug in the cpu connector? PSU could have killed MOBO as it was dieing. good luck




NOT

[NHawk]

I just has a similar thing happen on a computer here in the store.

If the computer has a video card that requires power (ie: AGP GeForce 6800) try disconecting the power to the card and turning the computer on. If it powers up, You have a bad video card.

If that doesn't do it, try disconnecting the hard drives, fans, etc. one at a time and repeat the process.

It's actually unusual for a power supply to go bad.

[1701E]

Depends on what Motherboard, Video card, and extra things you have plugged in.  If you have a video card needing 350Watts make sure it doesn't need a certain voltage (ex. 16A on the 12V rail).  If you have certain motherboards/PSU combos when a PSU dies it can take a Motherboard with it.  If the video card need a certain voltage make sure the PSU has it, if not the computer won't start (ex. Nvidia GeForce 7900 need 20A on the 12V rail...A PSU with 18A won't start it, unless you leave the PCI-E power connector unplugged).