With Windows 7 there’s not much you really need to do.
Windows:
- switch off system sounds
- switch ‘processor scheduling’ to background services (ASIO drivers)
- disable windows’ firewall
- disable the defragmenting harddrives schedule (better defrag manually)
- create a high performance energy scheme
Bios: disable the on-board soundcard (if there is one), lan/w-lan - whatever you don’t need.
That’s it basically.
There are many guides over the internet, i.e.
http://www.tim-carter.com/index.php?Menu=1&SubMenuId=22&ItemId=89