Most likely the old computers failed because of surges from outside the house.

If you have a true grounded outlet and use a surge protector or even better a UPS with surge protection that is the best that you can do.

A true grounded outlet is one that have a ground wire, or metal sheathing on BX or metal conduit that forms connects back to the ground on the panel. You can meet code by replacing ungrounded outlets with GFCI outlets or using an upstream GFCI or GFCI breaker, but that does not give the full electrical protection to surge protectors.

I have UPC unit and have replaced outlet and red light Is still comes on :(

What red light?

You need to give details.

What does the red light indicate. How often is it on? How long?

Light Is indicating "Building wiring fault" it's on all the time.

Your old wiring most likely doen't have a ground wire. That would be the fault.

How much will it cost to ground it?