Turns on but stays on with no screen?

Blue Cypher · 20 Aug 2008 at 10:47

Hi, i have just had to fit a new powersupply to an old pc, its an ATX powered mobo on it so i put an atx power supply in with the same ratings as the old one. However when i plug the power cable in the machine just turns itself on straightaway without me even hitting the on button! and worse it wont turn off till i unplug the cable. Also nothing shows on screen, the monitor just go's into power saving mode.
Anyone come across this before?

Help please!

J.B · 20 Aug 2008 at 11:57

Does the motherboard require and additional 4 pin 12V for the CPU or does the GFX need its own power?

The only other thing I could suggest is take everything out and check all the cabling.

Blue Cypher · 20 Aug 2008 at 13:17

Cheers, but unfortunately everything is plugged in correctly, the graphics doesnt need a pin for powere and i plugged in the 4 pin 12v already

RJC · 20 Aug 2008 at 17:38

What was the reason for replacing the power supply?
Sound like a faulty board, can you try the old PSU.

Gunda · 20 Aug 2008 at 17:51

could well be a short somewhere, try the powersupply outside the case, or even remove and re-mount the motherboard.

PhillyDee · 20 Aug 2008 at 18:22

Does it have a speaker connected? The Beep codes may help.