Take it back and ask them to correct the new issue.
To figure out if it's a virus, try out of those Live CDs. I use the Ubuntu one since no install or learning of Linux is required.
Bob
After changing chip on motherboard my comp run's okey. Before that it just cant start or if I could start it, then will surely goes off not before long.
BUT after that something happen, the keypad shows something on. It sometime ok and sometime not ok. Sometime I got to push 3 or 4 time to type a single character. At another moment it seems that particular key works as normal as nothing wrong.
It is something related to virus thread or else? And how to resolve it.

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