Mixing sata port types (sata/gsata)

I am looking to set up a WHS box with a 750gb hard drive as the boot drive, and six 2tb drives set up in a Raid-1 array.

My motherboard has 7 sata ports and is an ICH10R board, so it should be good to go. Except.....

5 of the ports are sata2 ports, and 2 of the ports are Gigabyte's proprietary gsata. I suppose this means I can't do what I want, as the six 2tb drives would be on two separate controllers?

So what are my options here? For my PCH SATA control mode I can choose between IDE, Raid(xhd), and AHCI. If I select Raid(xhd) then the gsata ports aren't even recognized.

Is there anyway around this?

Assuming not, what are my options? If I get a simple PCI SATA card with another 2 ports on it can I still set up RAID with some of the hard drives plugged into the motherboard and some plugged into the PCI card? At this point my setup would look like...

Motherboard Sata Port 1 - 750gb boot drive
Motherboard Sata Port 2 - 2tb drive in Raid-1
Motherboard Sata Port 3 - 2tb drive in Raid-1
Motherboard Sata Port 4 - 2tb drive in Raid-1
Motherboard Sata Port 5 - 2tb drive in Raid-1
SATA Expansion Card Port 1 - 2tb drive in Raid-1
SATA Expansion Card Port 2 - 2tb drive in Raid-1
Motherboard GSata Port 1 - empty
Motherboard GSata Port 2 - empty

Hence, the Raid array would be made up of motherboard SATA ports 2-5 and the two ports from the SATA expansion card. Will this work?