PSU on its way out?

Associate
Joined
22 Aug 2005
Posts
373
Location
Kent
Hi
I have a 600w OCZ StealthXStream psu in my system (E8400, Asus p5q mobo, HD 4870 1gg gfx, 8gb ram) thats been in there since Nov 2008. Its always been fine, however past week or so I've had a few issues. On a few occasions ive plugged a usb device in (iphone 5 and a usb drive) and the computer has shut down and wouldn't power back on. Removing the usb devices usually would allow the system to restart. On a few occasions the system wouldn't boot at all unless i removed all usb devices.

Does this sound like a psu problem? Or possibly to do with the motherboard/usb ports causing an issue?

Cheers
Pete
 
Wouldnt turn on again, checked inside for loose connectors, all ok. Unplugged all usb devices, still nothing.

I noticed occasionally when trying the power button the power light would flick on then go straight out again (system not starting) and one of the cooling fans at the back briefly starts to turn but then stops.

I waited 5 mins and tried it again and it started to boot fine, but shut down after about 15 seconds. Retried and it booted, plugged in a few usb devices and it shut down.
 
Tried removing cmos battery for 15 mins but still having problems.

With the system turned off the red light on the bottom of the mouse is flashing constantly and on the motherboard there is a green light labelled pb_pwr that is also flashing. Any relevance?
 
you should try running with minimal connections. e.g removing unplugging fans, hard drives etc.. to see if it works.

if not try replugging in most things... might help.

remove the gpu and try it.
 
The flashing pb_pwr indicates an overcurrent on the +5vdc standby power bus.. the bus comes on, overcurrents, shuts down and then tries to come on again.. over and over and over. A steady +5vdc is required for system boot up..

So, what could be wrong...???

Generally, this is casued by short somewhere... but exactly how a short could have occurred is unknown.

If you have any USB connections to the mainboard USB headers, disconnect them.. some cases have a front panel unit that is connected to the board by a cable... If you are using any USB devices... mouse, keyboard, drive... disconnect them.. see if the blinking stops and the SB_PWR LED lights steady.


OR simply your PSU has gone faulty too, if you can try another PSU to rule that out.
 
Last edited:
I disconnected all USB devices and any plugs from the front panel that plug into the USB pins on the motherboard, no boot up and still blinking green.

could I have shorted/damaged something on the mono when plugging a USB device in? How come the problem has been intermittant?

Since removing the cmos battery for 15 mins and replacing it, it doesn't seem to want to start at all now.
 
Back
Top Bottom