I just reinstalled 7 (64 bit) today and I'm already hunting for bug fixes.
I have a AMD 780G mainboard from Asus and the latest Vista southbridge
drivers don't install for me.
Another fix:
Windows 7 must run in IDE mode, not AHCI in order for the drives to show up.
Check BIOS for Sata controller mode something, it should have IDE, S-ATA and on some mb RAID as options.
Pretty simple solution that worked for me... after that I switched back to AHCI... the drives were missing again, but I'm done with that setting and moving on to the next bug.