Hello all, I was hoping you could help me end my debate on which of these two OSes to use on my gaming rig. At this point I only have a copy of XP64 and need to save up for the Vista copy. I've read several threads on 32 vs. 64 and a couple on 64 vs. 64 but what I'm looking for is a specific opinion on my system. So, without further ado: Core 2 Duo E6750 2.66GHz (BX80557E6750) ASUS P5E (with on board audio and networking) 4GB (2x2GB) crucial PC6400 (CT2CP25664AA800) eVGA GeForce 8600GT 512MB Seagate Barracuda 7200.10 320GB/7200RPM/SATA3.0Gb/s (ST3320620AS) OCZ GameXStream 700W SLI Certified CrossFire Ready Power Supply (OCZ700GXSSLI) Currently I am running XP Pro SP2 (32 bit) on the single HD. However, due to a multitude of errors none of my games work. At this point I just want to have a stable system that I can play my games on. I've heard that both 64bit versions are more stable for gaming, especially with the setup I have. I also would like to get the full value out of my memory (noting the 3GB max memory detection on 32bit OS installs.) So my question is, Vista 64 or XP 64 and why? I'm pretty sure my system is fully compatible and has 64 bit drivers available for all of my hardware. If you know otherwise please let me know though. A question of partitioning: I'll probably install xp64 right now on its own partition. Install games and programs on a second partition and then everything else (music, vids , etc.) on a third. Is there anything I should know about installing Vista that would affect this method? (i.e. partitions differently, or something with the file system) Errors and troubleshooting done so far described in more detail: Mainly getting nv4_disp BSOD errors and crashes from games to the desktop with a windows error report window. Updated all hardware drivers. Tried all nvidia drivers from the last year. Swapped out the 8600 for an ATI 2600PRO. I get similar errors with this board. I've tried disabling all the on board (audio, etc.) with no change. Games tried: HL2 (and related), Assassin's Creed, bioshock. Rollercoaster Tycoon 3 seems to work but often has graphics artifacts.