I'd talk with the PC's maker about what they want to do next.
So I left the PC at home while its installing 150+ updates from windows (win 7) I got back and turn the PC on but theres nothing on the screen and my keyboard and mouse wont light up. Before this happened, hw monitor shows that cpu temp is 90°C. I shut it down, windows install the updates before shut down, but I left the house because its going to be long wait. I came back and the problem started. Sometimes the PC boots normally (1 of 7 attempts). I tried removing the RAM stick and switched the PC on, but it didnt give the warning beeps. I also tried moving the RAM stick to a different slot, removing the graphics card and unplugging all usb cables but problem stays the same. Do you think the motherboard is the problem? If yes, can the motherboard be repaired instead of replaced?

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