In the BIOS, i went change the SATA to IDE mode (NOT RAID, NOT AHCI)
1.Boot Win7 DVD
2.Choose the Language Selection.
3.Choose Repair.
4.On the recovery tools choose the Command Line Console
5.Type:regedit <ENTER>
7.Highlight HKEY_LOCAL_MACHINE
8.File > Load Hive
9.Select < windows partition with problem > \Windows\System32\config\system (Backup this first, it’s advised)
10.Regedit will ask for a Key name: Name it something like “temp”
11.Located HKEY_LOCAL_MACHINE/temp/Select/Current
12.Searched for every key containing the value “SCSI Miniport” where the “Start” value was a “3” and changed the “Start” value to a “0”. (F3 to search next result).
13.Highlight “temp”
14.File > Unload Hive
15.Restart
16.Enter in Win7 🙂
vezi si https://social.technet.microsoft.com/Forums/es-ES/19c703a4-f52a-4b90-8a8c-fd80cbaf9c7a/windows-7-no-boot-stop-0x0000007b-and-classpnpsys-problem?forum=w7itprogeneral