One thread i found interesting:
There's no clear answer to this question but a few facts will help you:
- Live is currently a 32bit application but it will work on a 64bit Windows System.This means Live can only access a theoretical maximum of four gigabytes of RAM - regardless of how much you have in you computer. Additionally, Live can only access 32-bit third-party plug-ins.
For more detailed information about Live's performance under 32-/64-bit operating systems, please see: http://www.ableton.com/pages/faq/general_questions#faq_7_link
We have no information yet about if or when Live may be released in a 64-bit version.
- the more RAM and the faster your hard drive, the better in general.
- Live does not support hyper-threading but multiple Cores.
- make use of the vast experience of other users in our user forum http://forum.ableton.com
and test results from pc- magazines to find a suitable machine for you
- buy a professional audio interface with low-latency audio drivers