I would start by uninstalling/reinstalling drivers. Someone on a newegg review suggested installing drivers before installing the card. See:http://www.newegg.com/Product/Product.aspx?Item=N82E16814202011&SortField=0&SummaryType=0&PageSize=10&SelectedRating=-1&VideoOnlyMark=False&IsFeedbackTab=true#scrollFullInfo
Then I would check msconfig [start, run, type "msconfig" (w/out quotes)] and uncheck all NON-ESSENTIAL startup items. These items run in the background and may be using up cpu resources.
Also, I would download and install malwarebytes (you can get it from download.com). I would run a quick scan and removing any malware found. Then I would run a full scan, just to make sure.
Also, make sure your anti-virus is up-to-date and check for viruses. (by the way, I use Avast).