Messy Display

[henrytay]

I've a cumbersome time dealing with the display problem of RedHat Linux. I've recently had firsthand experience on Linux. However, when I started scrolling or moving the windows with my mouse in the Gui(Gnome) environment, my screen shows a mess of fragments of icons or windows here and there. It seems that when I drag something, it leaves a trail of pieces on my desktop. Can somebody help me with this matter?
Thanks!