Ableton Forum

Until they (if they) do release a 64-bit version of Live in Windows, there would be little if any performance increase. Also to keep in mind for anyone who might also be running ProTools and Ableton Live on the same PC, ProTools isn't supported on the 64-bit WinXP yet.

And how many folks have had a Windows system tank out completely after a simple driver upgrade ? (Never happened to me... -ahem-).

You could clip one corner by using a "free" audio editor instead of something like Sound Forge. Maybe put the money towards a nice Trigger Finger surface for laying down beats.
http://audacity.sourceforge.net