From the officail westwood tech support site ...
Question
What are the known Video Card Issues with Command & Conquer Generals?
Answer
Known Video Card Issues with Command & Conquer Generals
For optimum video performance, we highly recommend that you run Command & Conquer Generals with an AGP video card. PCI video cards are generally much slower than AGP cards, and you may experience abnormally slow performance and poor graphics with a PCI-based graphics card. Additionally, the video cards listed below are below our minimum supported specs.
• Leadtek Winfast GeForce 2 GTS (AGP, 32MB)
• SiS Xabre (AGP, 64MB)
• Gainward Xabre 400 (AGP, 64MB)
Additionally, Some Nvidia GeForce 2 MX owners may experience some stuttering problems during movies.
If you attempt to run Command & Conquer Generals at 1600x1200 with a 32MB Nvidia GeForce 2 video card, the game may crash to the desktop. If this happens, try reducing the game's resolution.
Under all resolutions, you may experience that some objects like trees, walls, and pillars will flicker briefly. If this happens, saving and reloading your game will resolve the issue.
And required system specs OS: Windows XP/me/2000/98 (windows 95/nt not supported); CPU: 800MHz intel Pentiumiii ar AMD athion processor; RAM: 128 MB; CD/DVD-ROM SPEED:8x; HARD DRIVE SPACE: 1.8 gig's free hard disk space plus space for saved games, widows swap file, and direct-X 8.1; video: 32 MB AGP video card using the Nvidia GeForce2. ATI Radeon 7500, or more recent chipset with Direct-X 8.1 compatible driver; SOUND: DirectX 8.1 compatible sound card; INPUT: keybord, mouse(duh)!!!