2010 Imac power supply ?

My Imac has issues that occured suddenly. All applications have multi colored spinning balls of death. I cant quit applications or shut down using normal methods.

Took it to Doctor Mac. He said everything was working fine. Yes at the shope all was fine using his power cord, mouse and keyboard.

Bought a new mouse took it home, same problems. Tried different outlets in my house…….same problems.

My Imac power cord looks fine……..could it be the power cord?