The 2 TB limit exists in a few different ways. The first, and hardest to deal with is the limit imposed by older RAID controllers. Since you are seeing a 2.7 TB volume my guess that you are not limited by that. The second 2 TB is a limit imposed by MBR. The workaround for this is creating multible 2TB partitions on the drive. Windows currently limits NTFS to 256 TB so we wont be hitting that at home for a couple months, heh. Have you tried converting your disk to dynamic or something like that in the disk manager. This might allow you to partition the remaining 750 GB. On the system that does not boot off the raid 5, why not just make the 2.7 TB volume a GPT volume and have one partition?
As far as I know you cannot install windows on a GPT so you are out of luck with the boot RAID 5 and any wishes to have 2.7TB of continuous space. If you are using Matrix raid why not just create two volumes? One for boot and one for storage. Lets say a RAID 10 of 200 GB for boot and then the rest RAID 5. This will present two drives to windows 7 during an install and it will let you use the rest of your RAID as a single GPT volume of around 2.3 TB. Another thing to think about is losing data on a boot partition. If you have your OS and data all on the same partition, what happens if windows becomes corrupt and you have 2 TB of data sitting on the same partition to deal with. I like to create a small parition for my Windows install, lets say 150 GB for windows 7. Then I use the rest of whatever drive I have left to store my data. That way, if I do need to complete a full rebuild, I have all my personal data outside of the boot disk. This way you can just wipe the boot drive clean and start from scratch with no worries.
The 2 TB limit exists in a few different ways. The first, and hardest to deal with is the limit imposed by older RAID controllers. Since you are seeing a 2.7 TB volume my guess that you are not limited by that. The second 2 TB is a limit imposed by MBR. The workaround for this is creating multible 2TB partitions on the drive. Windows currently limits NTFS to 256 TB so we wont be hitting that at home for a couple months, heh. Have you tried converting your disk to dynamic or something like that in the disk manager. This might allow you to partition the remaining 750 GB. On the system that does not boot off the raid 5, why not just make the 2.7 TB volume a GPT volume and have one partition?
As far as I know you cannot install windows on a GPT so you are out of luck with the boot RAID 5 and any wishes to have 2.7TB of continuous space. If you are using Matrix raid why not just create two volumes? One for boot and one for storage. Lets say a RAID 10 of 200 GB for boot and then the rest RAID 5. This will present two drives to windows 7 during an install and it will let you use the rest of your RAID as a single GPT volume of around 2.3 TB. Another thing to think about is losing data on a boot partition. If you have your OS and data all on the same partition, what happens if windows becomes corrupt and you have 2 TB of data sitting on the same partition to deal with. I like to create a small parition for my Windows install, lets say 150 GB for windows 7. Then I use the rest of whatever drive I have left to store my data. That way, if I do need to complete a full rebuild, I have all my personal data outside of the boot disk. This way you can just wipe the boot drive clean and start from scratch with no worries.