Thus, grub4dos can see sector 0 to sector 7814037167, that is roughly 3.9TB. And that is a good case - grub4dos (and BIOS) can access sectors beyond 2TB.
By the way, how many sectors in the whole drive (hd2), please?
emm..... Another test, if you don't mind:
Step 1. On Windows, use a hex editor to view a sector near the end of drive (hd2). Suppose it is sector N. (Note: You should choose a sector that does not contain all zeroes, i.e., not filled with only zeroes).
Step 2. Reboot and go into grub4dos, and run
cat --hex (hd2)N+1
where N stands for the sector number N selected in Step 1.
Step 3. Compare the 2 results, and see if they are the same.