Biostar

You should be able to fit in GeForce GTX 780 card on H55 HD board.
However, two PCI slots on motherboard will be blocked by VGA card's over-size cooling fan.

Here is the list for AM3+ motherboard to support two PCI-E graphic cards.

TA990FXE

TA970

TA970XE

Yes, please go to BIOS download section for update the latest BIOS and chipset driver to support Intel Ivy-Bridge E CPU.

http://www.biostar.com.tw/app/en/mb/introduction.php?S_ID=567#dl

Yes, both model will support CPU Smartfan function.

Our BIOS has a munu for setting the Smartfan or it can run automatically.

Intel H55 chipset will not be able to support 3TB hard drive with full disk space.

It's due to chipset specification limitation.

Also to support 3TB hard drive need to have UEFI BIOS.
However our H55 model uses AMI core 8 BIOS.

So it will not be able to support full 3TB disk space.

TPower X58 will not be able to support Intel Xeon CPU.

Clone view will only be able to work from single GPU. So Hi-Fi A85S3 will be able to do clone view with on-board VGA and on-board HDMI® port.

With add on VGA card, it can do extension view with on-board VGA and VGA card with two GPU.

Hi-Fi B85S3E will only support mSATA function. It will not be able to support mPCIE.

Our A880GZ will support up to PCI-E v2.0 VGA cards. ASUS GTX760(DCwOC-2GB) is PCI-E v3.0 VGA card. Due to  hardware support limitation A880GZ will not be able to support this VGA card.

Our Hi-Fi A85W's on-board audio codec ALC892  does not support DTS-HD and Dolby True HD Audio Format. It's due to audio codec's support limitation for support these two audio format.