weird behavior with pc

[Scitesh]

if I slightly tap the pc case or put my headphones on top of it ,the pc crashes or reboots.

I've double checked all the wirings to ensure nothing is loose .

 

this behaviour Is very interment and very frustrating to recreate 

the tower is on floor and powered by an ups 

[SpookyCitrus]

Sounds like a grounding issue with the case. You'll want to double check your motherboard is properly installed on the correct amount of standoffs. I'd also remove it from the UPS and floor just to rule out an external device or something with static from the floor causing it.