I didn't reformat my hdd but I wanted to make sure everything was running vid card, cpu, mobo so I just plugged everything in and turned it on no problems at all.... but when it gets right passed the bios where it normally would boot windows it asks to boot in safe mode etc..I hit one then procedes to crash is that because my hdd isn't noticing the new mobo.....all in all for my first time ever building a comp was fun and took about 4 hours or so after days of prep and reading thanks all who helped also.