Go into yoursteam, right click on all the games you have installed choose "Backup" back them up to your other drive, once you have done that for all the games uninstall steam. Reboot, reinstall it to the other drive.
Copy the backup files into the /steam/steamapps/<emailaddress>/backup folder
Right click the game inside steam, choose install.
All the games shoudl reinstalled very quickly.
Cutting and pasting the folder works, but ti can cause issues with files suddenly becoming protected as i discovered when i did such
