Also add the memory situation. DirectX uses the main memories which means it imposes on harddisks when the memories are full. Whereas, it is not the case in openGL which uses the ram on the display card -- in turn, display card does its work while the cpu and the hdd do their own. So, there is a more speedy and compatible system.

BUT I PROPOSE: Never buy or use these newly created Turbo-cache video cards. These also consume the main memories. They are said, for instance 512K but they are in fact 128K and when 128K is full, it borrows the remaining from the main ram. At these times, the system crashes. When you are told it is 512K, it means, in fact that they are capable of managing 512K. Read their manual on the net carefully.
