Don't do it. When windows is running it opens several files, and so do your apps. When you close down if there is insufficient space to save those files, your system will crash big time and you'll be doing a sector by sector recovery to retrieve your data. If you have a lot of ram and are daring........ you can disable your virtual memory, which should give you more hard drive space. You'll find that your system runs way faster right up to the point where it rams out and then it will black screen and reboot. Win can restore from ramming out but it can't restore from running out of HD space.