PC cut out

[Bradders050]

My PC (tower. CPU Intel 4, Win 7) keeps cutting out (like elect switched off). However when I lay the PC on its side on my desk it works fine - cuts out when I, gently, try and stand it back up. Or if I stand it back up and run it will cut out again.
Any ideas ? Is there like a 'tilt' ir trip switch that is triggering causing my PC to cut out ?

Thanks - Steve

[Old Rich]

and welcome to the Forum

Could be a loose connection inside . . open the case and reseat every power connection