after i alt tab, then go back to quake, i notice a severe drop in quake performance

also when i come back to quake, its lot darker. and i need to change gl_gamma but if i set it to the value i had before, the screen stays the same, but if i change it by .1 up or down, it resets to where the color should be

any1 know what causes or can fix the gamma problem or fps problem?

thanks

BTW using a radeon AGP, x1650

Same for me, exept the fps drops, using x4850

it starts dropping under 100fps ingame , that doesnt seem right

p4 2.9ghz 1gb ram 512mb x1650agp

original textures