I bought an HP about a year ago with what I assumed was a good video card: a 128 mb GeForce4 mx440 AGP 4X. But I have a lot of trouble with shifting colored dots appearing on my screen while playing games. I've downloaded new drivers, spent hours on the phone with game/computer/monitor tech support without finding a lasting solution. Do I just need a new graphics card? If so, what's a good moderately priced one? (I'm not a hardcore gamer, so I don't need top o' the line.) Thanks.