Okay, heres the lowdown: I dual-boot both Windows XP Professional and Windows Vista (OEM), both 32-bit. Both are freshly formatted. Both operating systems work great, no issues to report. Both have their own partitions. I have installed Halo 2 on both operating systems. Naturally, the game is supposed to be only available for Windows Vista, but through my networks of pirates and hackers, I have come across a hack that has allowed me to install and play it on Windows XP. Now, the problem: When I play Halo 2 on Windows Vista (Which it was made for), the graphics are extremely slow and buggy, as well as choppy and jagged. Windows Vista allows me to use the NVidia control panel to adjust the 3D settings of various installed programs on the computer. It doesn't matter what I have it on, default or otherwise, the graphics are always dumb like this on Vista. Halo 2 also allows me to change various video settings in the game, and I change them to reflect 'best performance' (such as disabling anti-aliasing, turning down effects to Low, fixing the screen resolution at 800x600 -- full screen or windowed). Now, when playing on XP, there are no options like this available except for inside the game, so no NVidia control panel. The game runs absolutely flawlessly on the absolute highest settings. However, in an effort to play online, the hack does not allow for various things such as GFWL (Games for Windows Live) to work, therein my dilemma. What can I do in Windows Vista to make the darn game work? XP is fine, but is there maybe some kind of hotfix published, or someone who knows how to decode the problem? Here are my system specs: Processor 2.0GHz AMD Athlon X2 Dual-Core QL-62 Memory 2GB DDR2 Hard drive 250GB SATA 5,400rpm Chipset AMD RS780M Graphics 256MB Nvidia GeForce 8200M Operating System Windows Vista Premium (32-bit) NOTES: (Vista) Computer is fully updated, Windows and Microsoft products, including updates to GFWL for Halo 2. No anti-virus installed. Security center and all applets disabled. System restore and Windows Backup disabled. (XP) Also fully updated. In Windows XP, the system specifications show that the GeForce 8200M has 512MB dedicated video memory. Both XP and Vista are using the same version of the driver, just downloaded the seperate versions for the OS' respectively.