As far as I understand, you are trying to boot up into the Operating System that's installed on a 2 TB. hard drive. If so, I confirm there's a limit on boards using either the Intel® 82801GR I/O Controller Hub (ICH7-R) or Intel® 82801GH I/O Controller Hub (ICH7-DH) [this includes the Intel(R) Desktop Board D975XBX2 (see page 12 of the Technical Product Specification here)]. For more details, please, refer to the following URL:
Anything less than 2 TB., for booting, should be fine.
I realise this is a duplicate post for another which has other replies (including one from me). I realise that in order to get OVER 2 TB in a volume to boot, a UEFI configured motherboard with a GPT setup on the HDD is required but I thought 2 TB (as opposed to over 2 TB or between 2 -256 TB as another way of putting it) was still supported.... If 2.0 TB itself is not supported, what is the precise limit (if the WD drive used by the OP is only a tiny amount over the limit, maybe another 2 TB drive which is a few MB smaller may work)? FWIW both my RAID 10 setup with 4 x 1 TB Samsuing HDDs and my single Samsung eSATA drive all show up in Windows at 1.81 TB (ie under 2 TB) even though the number of bytes is shown starting with a 2. I've included a screen shot.