I have an HP Pavilion 7850 and it will not boot up. I have unplugged the machine and tried a new outlet but that did not work. As soon as I plugged it in there is a green light that will flash on the back of the machine but that is it. Can anyone point me in the right direction?

We need more info as to what "not boot up" means.

Fans on?
Disk spinning?
Which light flashing on back of machine?
Does it stop flashing?

The computer will not start up at all (the fan, disk, everything will not start up). The only thing that it does is right when I plug it in, a green light next to the power cord will flash.

Any clue what I should do?
Thanks so much for your help!

Either your PSU is dead, or a fuse has blown if it's fitted with one (what was the cause of thet?).

Did you fit anything onto the PC that took it over the rated PSU?

You can try exchanging PSU with a new one - not difficult DIY. You won't get it going without dealing with one of the above suggestions.

A further piece of advice:

To buy a new PSU, take the old one out having first photographed its connexions to various devices and the motherboard.

Then at the shop, make sure that the motherboard connector is the same.

They're cheap enough so uprating the PSU in terms of wattage won't hurt and you may have no choice given the age of your existing PSU.

Keep us posted.

Hi All,

I have a desktop PC - HP model: A1240N socket 775 with issue not power on it believe PC was so dusty and show indicate power fan will go bad. So it happen shut down which I unplug all power connector than clean dusty out from the PC unit. I'm ready to reconnect all power cord correctly that nothing turn on. Start troubleshoot these steps:

1) Switch power supply
2) Use different power cord connector
3) Just plug keyboard, mouse, hard disk, cpu
4) Testing serial port plugin laptop it have power image display
5) Hard drive still fresh
6) Detective a 4pin cable 2 black/2 yellow wire it belong to power connector that
generate output into motherboard next to CPU fan. When I do unplug it will power
supply fan/cpu fan is running but no image display on monitor whatsoever. If the 4pin
(black/yellow) left it connect to the motherboard and completely dead.

Please help me further troubleshooting this issue and I'm appreciate of your time.

Thanks in advance.............

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