The computer fails to power on and causes a circuit board malfunction.
The computer fails to power on and causes a circuit board malfunction.
As I said, you can run it without a fan, but you do need a heatsink, and if it's not properly seated it will be hot. Since you can see the temps drop just by applying pressure to it and you say you don't have the proper mounting kit, I'd say it's a good chance that's your issue. You need to properly secure it then go from there. But if the computer starts, you're probably fine. Just be careful pushing the cooler manually; you might push it in a way it's not designed and break the board. As for why it's not tripping the breaker now, sounds like there was a short somewhere, which is now not shorted after removing everything. Just need to do a thorough inspection of the PSU cables, look inside the PSU or gently shake it to see if there's anything loose inside, check other cables for damage, look for any burn marks indicating where something may have shorted, etc. Edit: And as cyberat mentioned, definitely get a UPS.
It isn't verified it was the PSU. Could have been another component, and swapping it might not solve the issue. I think it's a good idea if the problem persists, even though it functions on a test bench. It makes me wonder if another factor contributed to the problem.