I saw this http://www.tomshardware.com/forum/256287-32-adding-boot... and thought YES! Someone with the exact same problem. I put a second drive into my asus g75 series laptop running win 7 64 bit and I get a boot error exactly as the guy did in the above link. My problem was the same. Yet when I tried making sure my primary drive was listed as first in its boot order, it didn't matter. Still boot error. I remove the disk and everything works perfect. I don't get it.. Any other help?