I made a game with nice view - panorama mountains. It is a bitmap 4096x512 pix it looks very nice. But when I use ATI RADEON 9200 64MB card, it start problems. Some parts of my panorama bitmap disapears and sometimes all the bitmap disaperars, when I turn the player. I didn't have this problem even on older card NVidia Geforce 2 200 (32MB). Is there any possibility to solve this problem or only to buy older graphic card?

I have newest drivers, newest directx