Flickering (Again)

Hi AllHope this is the correct forum, otherwise mods please feel free to move it to a more appropriate location. I have an ATI 9800 card. Everything was working fine until I installed Ground Environment and then, later Flight Environment. I am now suffering with the dreaded flickering textures - usually over water, but sometimes over land as well. It looks like there is a fog layer on the ground, but it shimmers and flickers. It is only visible in the region under the aircraft, not in the distance.Have fiddled with a few ASV6 settings and with FSUIPC (3.72), but no joy. Have fairly up to date drivers as well (Catalyst)I have heard that ATI 9800 cards do get heat exhaustion and develop problems, could this be the problem?Thanks