Sorry guys I'm no techy here so bare with me... If I were to upgrade my graphics card from a GT630 to a GTX630 would that fix my problem? and if so, how can I check if my motherboard will take that graphics card?

In my original post where I mention "forums with worse spec pcs" I actually didnt realise that the "X" in the model number made that much of a difference... I have only had the pc for a couple of months, so thought it would be a more "up to date" graphics card...