Unable to put "Texture Detail" Slider to max

It seems that every time I move that silly little slider over to the right/max and click accept, it instantly reverts to the default(middle) setting, not allowing me to use the higher quality textures. If I go back into the options menu, lo and behold, it's back to the default. This doesn't happen with the other sliders.

Is there a config file I could manually edit? I'm running a Radeon 6870

There is but is your world detail high enough?

I made the switch to Windows 7 last night and the problem seems to have vanished.

Thanks for replying though. Have a good one

You too.