Think I need a better video card. Getting ready to purchase a couple of desktops with Intel i7 processor. This is a biz computer using a single thread software that ties into excel with dual monitors. Other than that it uses internet, MS Outlook, and Yahoo IM. The Yahoo IM has between 60 and 70 boxes open at the same time. Would getting a better dual video card improve the performance and speed of the computer? What video card do you recommend?