Half-Life was the only game that really made me sick after playing it for awhile. My stomach would just start to feel queasy and I would have to stop playing. Now, I have been able to play other games just fine, even CS. I don't know if it was the colors or the infamous refresh rate problem with nVidia drivers. Since then I have applied the patch to fix the refresh rate but I have not played Half-Life since then, only CS. All I can say is that you have the refresh rate set high enough and that you are getting respectible FPS.