Pc Won't Start, When Booting Fans And Leds Run For A Second Then Drop Out.

The previous day to this post an electrician came over to install ceiling fans and in doing so he turned the power off while my PC was running, it kept running although lights and some wall ports didn't work so I don't really know what he did. The next morning (today) when I try turn the pc on the fans run and leds for about half a second then die. I'm guessing something has shorted.

any help would be greatly appreciated! Thanks, Patrick.

What I've tried as of today:

• booting without USB accessories plugged in
• booting without hard drives
• booting without GPU
• booting with 1 ram stick tried in different slots
• replugging PSU cables and mobo cables
• Taking out mobo battery
• cleaning ram sticks
• dust cleaning everything

System

CPU: I5 6600k GPU: MSI GeForce Gtx 1060 6Gt Oc Mobo: Asrock Z170 Pro4/D3 Ram: Kingston Hyperx fury 16gb DDR3 (2 x8gb) CPU cooler: Hyper 212 Evo PSU: EVGA supernova 750w

 

try a power flush. unplug the pc from the wall outlet and hold the power button for 10-15 seconds. Then plug back in and try to power it on. See if anything happens.

 

Sorry, but that's an old wife's tale. But like most myths, it has roots going back to some truth. Unfortunately, that was over 20 years ago with the "AT" Form Factor PCs as used by the original IBM PC when the front power button was wired directly back, through a wiring harness, to the AT style power supply.

But in 1996, the "ATX" Form Factor standard became the industry standard for PCs and is still the standard today. And holding the power button down on a "ATX" PC does nothing but make your finger tired. This is because it is really a remote button that simply shorts two pins on the motherboard to signal the motherboard to "change states" (on if off, off if on). There are no storage capacitors in that circuit to "flush" or bleed off any power. And since that button does not connect directly to the PSU, it has no effect there either.

HOWEVER, unplugging from the wall for a few seconds (or setting the master power switch on the back of the power supply (if it has one) to off (0) does totally shutdown the power supply and remove all power from the motherboard, so that is a good idea.

"Some" notebooks, on the other hand, do benefit from holding down the power button. That step is used some times to calibrate the battery charge monitoring circuits. But this is a PC, not a notebook.

That said, I assume (hope!!!) the OP unplugged from the wall before reseating all the PSU and mobo cables.

More probably a surge.

What you need to do is verify you are supplying good power to your components. That would require swapping in a known good PSU and see what happens. Also, every home and every computer user should have access to a AC Outlet Tester to ensure your outlet is properly wired and grounded. I recommend one with a GFCI (ground fault circuit interrupt) indicator as it can be used to test bathroom and kitchen outlets (outlets near water) too. These testers can be found for your type and voltage outlet, foreign or domestic, (like this one for the UK) at most home improvement stores, or even the electrical department at Wal-Mart. Use it to test all the outlets in the home and if a fault is shown, have it fixed by a qualified electrician - probably not the same one you just used.