I just paid $145 for XP pro/SP2 OEM at Newegg. Seemed a bit high, I thought. With all the different designations, descriptions and packaging that Microsoft and its resellers use, I guess I am not crystal clear on whether I am getting the right version for my new, from-the-ground-up build, for personal use only. Seems like a dumb question, but not for someone who hasn't had to new a total new build before. This pricegrabber site seems to offer what I think is the same one, (for alot less $) just want to be sure. Also, are there limitations (in terms of upgrades, compatability, licensing, etc..) I need to know about? According to microsoft, the 'oem' version is for new builds that have no os yet. ("builder's license") Need to know, because if I just foolishly paid twice what I had to, I will try to return, or at least shop elsewhere for my next XPpro purchase. tia for replies 