Howdy,

Went to put some hot cross buns in the toaster..... tripped the safety switch. I reset the safety switch....

Went into the office and the PC was off (it had previously been turned on). Tried to turn it on, but would not start up. I assumed it was the power supply. However I noticed that the light was on where there ethernet cable was plugged into the machine. So power was getting to the MB.

Opened the machine up and had a look to see if I could find anything obviously wrong. Plugged the power cable back in, and tried to turn it on again - no go. Unplugged the power cable, and then plugged it back in. Power supply fired up, as did the fans on the MB and CPU.

Put side back on case, and then plugged all peripherals back in. Repeated same turn on procedure. Nothing comes up on screen, no noises like normal boot up etc.... I.e. no bios check, ram check etc...

So not sure if it is power supply, motherboard, hdd, graphics card.

Any thoughts?

Start with as little plugged in as possible.
Try one peripheral at a time. Your damage could be one of many things, so you must use process of elimination. Be patient.

My money is on the PSU. Spinning fans doesn't mean that the PSU is working properly.

Second guess would be VGA. Fried VGA would cause some beeps too. (1 long 7 shorts)

Third guess is RAM.

(etc.)

As Mike said, process of elimination is the ONLY way to single-out the cause.