A new problem discovered running Solaris and Red Hat Linux development environments, these do not seem to like the wierd MBR partitioning scheme Windows 7 creates and will not install unless it is a MBR that XP, Vista, or Linux created.
Linux does not require EFI to create GPT partitions and developers are not usually given Itanium blades, let alone server addition for application development.
While Windows 7 diskpart allows you to format a GPT drive it is intended to format a secondary hard drive. If you format a GPT primary and return to installation, Windows 7 setup will prompt you to reformat the partition NTFS or MBR and Continue Setup remains greyed out until you do.
No problems installing Windows 7 on GPT. You must convert the HDD to GPT during windows installation and you must move forward without creating a partition, i.e. unallocated partition.
Trying to build a realy big software raid, the two devices are 2.7T, and I cannot use msdos like partiotions, so I tried GPT, the kernel is compiled with GPT partiotion support, I have /dev/sda1 that is /boot partiotion and an software raid1 /dev/md0 (/dev/sda2 and /dev/sdb2) that is 2.6T, I used parted, of cource to manage the disc, the the raid partitions are with flags RAID, the boot partition is with flag BOOT. Also the grub is compiled with a patch and now grub 0.97 recognizes the GPT partition like tables. So I boot, grub screen, I choose kernle, the kernel is booting, and then the errors:
invalid raid superlock magic on sdb2
sdb2 has invalid sb not importing
invalid raid superlock magic on sda2
sda2 has invalid sb not importing
...... autorun done
reiserfs: md0: warning: sh-2006: read_super_block: bread failed (dev md0. block2, size 4096)
kernel panic - not syncing: VFS: Unable to nount root fs ot unknown-block(9,0)
(Core 2 duo)