That won't be worth it. If you read the MS knowledge base, it'll only assign 3GB RAM to applications that were explicitly written with the server OS in mind. Plus, with the correct start option, you can make XP do the same. If you plan to use a RAID-0, then, for the love of god, MAKE BACKUPS! Everyone tells you a RAID-0 makes it faster, but many don't tell you that it'll also be faster at losing data. When one drive in you RAID-0 fails, the data on all the drives becomes useless. Using two hard drives in a RAID-0 means it's twice as likely fail as if you had just one of these drives.