Presario 2800T - ATI Mobility 7500 rendering problems

I just recently purchased a Presario 2800T, P4 - 1.5 gig, 40 gig hd, 512
meg ddr ram,  ATI Mobility 7500 . I'm using rh 7.3 which comes with the
latest XFree86
 
My problem is when I load Xwindows the display has some issues
The only way I can explain it is that somehow my computer did not
completely render the display.
 
Remember the old interlaced gif that would render a little bit at a
time, that is what the graphics and text look like on my display. The
graphics and text are not completely rendered so I can make out parts of
what the text says but very hard to read. Parts of the actual window
look fine especially where there is solid colors like the background. 
 
I tried different combinations of Generic Laptop Display Panels but to
no avail. I also tried different resolutions 640*480, 800*600, 1024*768.
Can anyone help?