Question PC "no signal" upon booting?


Have an issue where a PC is powered on, but no signal to the monitor. Problem is not consistent though – after unplugging the power cord for a while, sometimes it works.

Specs. are a 2014/15 Pentium G, 4GB DDR 3, Asus H81M+ mobo, Corsair 430 watt PSU.

Troubleshooting so far:

  • Checked seating of all cables and RAM.
  • Tried swapping RAM to different slot
  • Power cycled
  • Tried brand new PSU
  • Tested RAM with MemTest86
  • Reset CMOS by removing battery.
  • Tried different monitor cables (DVI and VGA - have not yet tested with an HDMI connection)
  • Ran Crystal Disk on the HDD - no problems
Funny thing is, it's fine when just restarting (as opposed to powering down completely and starting up again). But if I try to boot from scratch twice in a row, I get 'no signal'the second time. Only way to get it working again is to power down and unplug for a few minutes.

Any advice is gratefully received at this point. Pulling my hair out!
Well if there's no BIOS image it won't be a Windows issue. Is there no card in this system? After all the steps already tried I'd guess it's a motherboard issue. It may be worthwhile to see if tossing in a cheap VGA card will resolve it before replacing the board.


Well, it seems the problem is resolved, though I'm not 100% what fixed it. Late last night, decided to have another crack at it. Decided to update the onboard VGA drivers (although at that point I was using an old 5670 GPU for video as that worked intermittently). I also flashed the BIOS to the newest version. Et voila, all was well. Left it running overnight, tried a few time this morning, all was good. Tried switching back to onboard video...and same problem. Odd! So, since then I've been powering up and down with the GPU connected and no problems at all. I feel like, based on some things I've read, that the BIOS update probably helped, but that still doesn't explain why the onboard video still has the problem.

Oh well, all seems ok now. Thanks for your advice, really appreciate it.