HP Pavillion p7-1299c won't turn on

[larrythelabrat]

I have an old (10+ years) HP Pavillion series desktop. It won't turn on.

We were getting some brownouts due to a storm, so I powered down the computer, but now it won't turn back on. 

The green light at the back by the power cord is on, but I get no response when I push the power button. No fan. No LEDs powering on. Unresponsive.

I've tried unplugging it and holding down the power button for 15 seconds and then plugging it back in and pressing the power button. Still doesn't turn on. (The green light on the back goes off when I hold down the power button when it's unplugged, and comes back on as soon as it's plugged in, but no other changes.)

I've tried holding down the power button while it is plugged in. No effect. 

The HP forum won't let me register the device via its serial number, possible because of the age of the system? I've found it, but their auto-check says it's not valid.

[BeemerBiker]

Hold it down for 20 seconds and count to make sure it's 20.  if you do it a second time and nothing happens then I'm afraid you've got hardware problems.

You could test the adapter and see if it's got the correct voltage but I suspect the problem is the fried motherboard due to a surge.

[larrythelabrat]

Yeah, even 20 seconds didn't do anything different. I don't know why the adapter would be the issue since it hasn't changed.

It was plugged into a surge protector; but something is wrong so maybe the motherboard did fry.

Thanks anyway.