A system I built for someone else a year or two ago, originally Win 7 but now upgraded to Win 10. They had been having trouble with the video not showing up off and on when turning on the computer (while I was out of the country) and now, in the middle of a Windows update process, nothing shows on the monitor at all and while the fans do spin, there is no POST beep (and the little speaker does work, see below).
Things I've tried so far without success:
1. Swapped monitors and cords
2. switched from VGA on the basic graphics card (doesn't need a PCI-E power cord) to the one on the motherboard, both several times and with/without the card installed
3. tried the DVI instad of VGA,
4. removing/reversing sticks of RAM. Tried each of the two sticks alone with no change, but with both sticks out I got the triple beep that I assume is to tell me there was no RAM installed but at least I know the onboard speaker works.
5. Tested the PSU with a multimeter, both the 24-pin and the 4-pin with the connectors loose and underload when attached to the MOBO, nothing looked bad
6. removing all connections (USB, network) other than the power and video cord
6. hitting all the F keys I can to try and get it to boot to BIOS, but get nothing to come up
I really thought it was going to be the PSU. Next time I go over I thought about pulling the CMOS battery to do a reset and bringing some sort of boot disk to see if perhaps the BIOS is corrupted, but I'm running out of options that don't include replacing the MOBO and the major headache that would cause. Any other ideas anyone might have would be appreciated.
Thank you for your time