Problem with computer graphics Icons disappearring programs failing

Hi i was recently called over to my aunties house to look at her pc she had been having problems with her onboard graphics when hovering the mouse over icons or links they would disappear almost like embedding themself into the page also microsoft office kept crashing everytime you turned it on so she was told by a friend to install a graphics card so i went round and did that and the problem seemed to be much worse! the blue windows load screen turned pink and the icons disappeared even more this sounds to me either like a motherboard fault or a RAM fault

Shes taken it to a shop they have ran tests on it and have come to the conclusion that the hard drive needs replacing as this is what is causing the problem, all sounds a bit far fetched to me sorry i dont have the specs of the pc

I have stopped her shes going to collect it now i would love to see what happens if he had installed a new HDD and the problem would have more than likely continued or maybe its just a good way to get more money out of a person which i dont agree with at all

Its not the GPU which is faulty as i took it back out when the problem got worse i suspect a possible bad board

Thanks for the reply Britton30 she has now decided to stick with her windows 8 (eugh) laptop and not throw good money after a problematic pc