Here's why.
" I can only start the PC with a screwdriver across the appropriate terminals on the motherboard "
This points to a future issue where some static discharge will damage the motherboard and remove the problem altogether.
Ouch.
Bob
Not sure if I have the right Forum. Apologies if not.
Picture this: Resident in Kenya where the national grid power is wacky to say the least. Huge power surges and multiple power failures per day. An industrial back up generator that kicks in when the mains fails. A double mains outlet socket (so 2 sockets)on my wall. All this is nominally in the 220 - 240v range like UK power.
I have 1 UPS in 1 socket, with my PC and monitor attached. PC has a 450w power supply. Another UPS in the other socket with a range of peripherals that draw low power or are only turned on when required.
Both UPS have 450 - 500v output.
Now, in order to be able to turn on my PC, I must turn OFF both UPS, turn on only the one that supplies the PC and then turn on the PC. Once that has fired up I can turn on the other UPS and any peripherals I need. No other sequence or combination will do.
This has only started happening recently and it started gradually, with the PC failing to start sometimes & OK other times. Now it will only work this way. It isn't something simple & distracting like the ATX case switch as I have been through & eliminated that kind of thing. I can only start the PC with a screwdriver across the appropriate terminals on the motherboard IF I go through the UPS sequence. I have also swapped with other UPS (everything we own has to be on one or it just blows up). Which component is faulty?

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