I have an Alienware M17x that dual boots into Ubuntu 11.04 and Windows 7 Home Premium. Currently, the computer starts at the GRUB loader and will boot into Ubuntu, but if I try to boot into Windows, I immediately get a black screen with a blinking cursor in the upper left corner.

The output of fdisk -l is

     Device Boot      Start         End      Blocks   Id  System
/dev/dm-0p1               1           5       40131   de  Dell Utility
Partition 1 does not start on physical sector boundary.
/dev/dm-0p2               6        1918    15360000    7  HPFS/NTFS
Partition 2 does not start on physical sector boundary.
/dev/dm-0p3   *        1918       64772   504878877+   7  HPFS/NTFS
Partition 3 does not start on physical sector boundary.
/dev/dm-0p4           64772       77827   104858625    5  Extended
Partition 4 does not start on physical sector boundary.
/dev/dm-0p5           64772       67204    19531008   83  Linux
/dev/dm-0p6           67204       74498    58593536   83  Linux
/dev/dm-0p7           74498       77577    24731648   83  Linux
/dev/dm-0p8           77578       77827     2000128   82  Linux swap / Solaris

I have used the Windows rescue CD, and run the automatic error fixer until it finds no errors. I have run chkdsk /R on both the main Windows 7 (/dev/dm-0p3) partition and the recovery partition (/dev/dm-0p2). I set the main Windows 7 partition to be active. I also tried running in the recovery console the commands

bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcd

None of these helped and the last set of commands deletes grub, which I then have to reinstall from Ubuntu.

I think the last thing I did in windows before this started was install the newest ATI driver for my video card. This would suggest using system restore, and I actually had a restore point earlier (after the problem started), but after whatever I did that restore point does not appear in the list on the recovery disk any more, so I cannot do a system restore.

Is there anything else I can try to make Windows boot properly again?

Edit: Running the suggested commands

bootsect /nt60 c:
bcdboot c:\windows /s c:

was also ineffective.