Power issue... I think?

[jrsonlakeview]

Having trouble an older Dell Optiplex 740...its runs WIN XP pro......Every time I power it up it goes through boot then turns itself off.....Can anyone help me??

 

[Route44]

How much tech knowledge do you have and/or do you have friend who can help? An easy way to test if it is your power supply is to use a multimeter.

Another thing you could do is to detach all peripheral items such as DVD drives, monitor , video/sound cards etc. until you have only PSU, cpu and RAM installed.

Boo up and then one at a time attach a piece of hardware and boot up. Keep doing so until you experience your issue.

 

[TypeIV]

Do what Route44 suggests. Does your system even begin to load the OS? Are there any beeps from the computer before it shuts back down?

I would say it's probably the PSU, where it provides enough power to allow the motherboard to test the functionality of all parts and get past POST but once the OS loads and powers up all the peripherals (CD/DVD drives, USB devices like your mouse, hard drives, floppy disks, video cards etc.) your power supply fails.

 

[dividebyzero]

PSU check.
If the system initiates a boot but doesn't complete then I'd also check the onboard CMOS battery (i.e. replace it)

 

[jrsonlakeview]

thanks but already tried that, system doesn't even beep, just shuts down............right before the OS comes up!!!