Question PC problem

Feb 27, 2021
I have a friend that recently hit hard times and had to leave his desktop in his car for a few months. He lives in NC and hit freezing temps some days. Well he tried firing it up after waiting a few hours indoors and nothing happened. What's his next step?
there's no telling what could be the culprit after treating a desktop roughly or moving it around that way.

devices unseated; CPU, RAM, PCIe\extension cards, battery, etc
cables knocked loose; PSU, front panel, etc
humidity damage
physical shocks causing hardware damage

if it's just an unseated device\cable;
the entire system may need to be disassembled and reconfigured to find the culprit.

a major system device may be damaged that would have to be replaced.
the best way to troubleshoot devices is to have a functioning compatible secondary system to test each piece of hardware in one at a time.