direct 3d refresh problems

[mgreen2]

I am having problems with my refresh rates when I run direct 3d games. When I start a game the picture is compressed or sometimes moved to one side or way up or down. When I go back to windows the desktop will be messed up too. My monitor refresh rate is set to optimal. Here is my system specs:
Celeron 700
256 ram
geforce 2 Mx 400 14.10v drivers
win 98 (fresh install)
direct x 8.0a

thanks for your help