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I recently built a new computer using an ASUS motherboard that uses an AMD processor. The board uses a UEFI firmware instead of BIOS. So wanted to use my RAID 0 volume which is 3TB as my primary storage.

The problem is when I go to run Windows setup from the DVD and get to the disk partitioning tool it wants to split the disk. It makes a 100mb reserved partition automatically which is expected. Where the problem is when I makes the system partition, it makes a partition that is around 2TB and then leaves about 750GB or so of unallocated space.

What gives! I thought UEFI was supposed to solve this problem with the 2TB barrier?

Is there something special I have to do with the Windows installer?

I have tried doing all kinds of things with diskpart last night and got nowhere. It said I needed to convert the disk in a GPT first then install. The problem is I do that then the installer overrides and does the same thing I said above about splitting the disk.

I don't want a system and data disk, I just want one massive volume.


Oh yeah if it helps at all, the board I have is an ASUS Sabertooth 990FX

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Make sure your DVD drive is plugged into an SATA III port, not an SATA II port.

When you boot your system, press F8 to use the UEFI BIOS boot menu to select your boot device.

In the boot menu, you should see your CD/DVD drive listed twice, though not necessarily sequentially. Choose the one of the two entries that has UEFI listed in front of it to boot from the Windows 7 DVD.

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Yeah I didn't see that option. But I know I specifically plugged my DVD drive into the SATA II ports. I will give that a try. – ianc1215 Jul 16 '12 at 17:45
You don't get the UEFI option unless the DVD is in an SATA III port on this particular motherboard. And if Windows doesn't boot from UEFI, then it won't let you make a partition larger than 2TB... – Michael Hampton Jul 16 '12 at 17:48
Will the fact that I have the RAID option rom enabled make any difference with the CD drive plugged in to the SATA III ports? – ianc1215 Jul 16 '12 at 17:49
Nope, no difference, as long as you actually have a free port to plug the DVD into :) – Michael Hampton Jul 16 '12 at 17:50
@Solignis - That is the problem. – Ramhound Jul 16 '12 at 17:52

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