read some of these reviews for Vista 64bit:
Pros: Looks Slick, has chess, so secure you can't even install anything without being asked twice!
Cons: Slower on the same system than XP SP2, Huge system hog, constantly buffers ram without increasing performance noticeably, 64 bit version seems compatible with nothing, not installers, not drivers, not programs, not even FSX on the desktop. This DVD is a drink coaster honest, I have owned it for 24 hours and I have decided XP SP2 is a better value for compatibility, performance, and speed.
Other Thoughts: Running on a Core 2 Quad Q6600 2 GB PC2 DDR2 6400 RAM Geforce 8600 GT, Vista scores are all 5.5 or better and the visual performance is decent but without being able to run anything on it, forget it. Been using computers since 1988, yes 19eighty eight. Not totally dissapointed but this still isn't ready for even monster systems. Very Sad. I'm a substance man not a style man!
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Pros: It only looks nice.
Cons: Windows Vista is a flop. Microsoft is aware of it and doesn't want to do anything about it. At first I couldn't install the driver for my video card but it seemed to work without it. Then I attempted to install my printer with the same outcome. finally, it simply refused to install every application while just giving a stupid message ""the programs stopped working and windows is trying to find a solution."" The solution is to contact the manufacturer of the given device or product. It became unbearable when IE7 refused to display yahoo pages, samsung, and even microsoft.com support page. I tried to install firefox with no success. Hence i decided to call the infamous microsoft support team (based in I N D I A). After spending 2 hours on the phone while they were looking for a solution they offered a downgrade to Windows XP (oh irony).
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Pros: Windows explorer is more feature laden, but nothing included is worth the price, especially for this ""Ultimate"" version where they consider offering language packs as ""features"".
Cons: constant hibernation and recovery problems, has lost RAID drivers and volumes repeatedly, Direct X 10 is unstable and problematic with Nvidia 8800GTX, Vista loses connection with it's USB ports and devices when recovering, VISta product license security has required me to call and beg an Indian help desk clerk on FOUR occasions since July to re-register the software because I updated video and Intel RAID drivers and it decided I was a pirate. It's incompatible with many applications and devices, the 64-bit version of IE isn't compatible with FLASH files, and the security system requires twice as many steps in almost any action.
Other Thoughts: Do your self a favor and don't buy this. I've been in IT since the late 1980's and this is the worst O/S I've worked with.
and it goes on, and on, and on.......