Personally whenever I upgrade I usually do a major time backup to an external HDD, and then wipe the slate and start fresh since I don't trust upgrades (know some people with some bad results of that), then I go on a reinstalling spree of all my programming. What was weird was that when I went to Win 7, it gave me the clean install upgrade option, which I expected it to just format my HDD and restart, which it didn't, it migrated all the old windows to a windows.old directory and installed this one. I would've used XP on my laptop instead cause I tried to install it clean before, but I think my laptop was rigged against it (don't buy Gateways; they suck ><). Since XP didn't have SATA recognition in it's setup without your BIOS allowing you to go into legacy IDE mode, it would not detect my hard drive. And my bios was designed to not allow you to go to legacy. So in order to install XP I had to use a splicing program to modify the XP setup CD with a SATA driver built in, and it eventually worked. But then my graphics adapter (ATI Radeon Mobility HD2600) did not have proper win XP drivers available for it. So in the end I had to give up and go back to Vista T_T. But now Windows 7 came out and it's been working absolutely perfect for me so far.