I usually leave the loop running overnight for leak testing! Just the loop not the whole PC on(using a spare PSU & jump start using a paper clip)
So are you saying your pump was off while the whole PC was ON? For how long?
Get a speaker on your motherboard and listen for beeps when trying to boot
What PSU you get?
this thread has made me laugh quite a lot, but I'm looking forward to seeing how it looks when it all eventually works