New HDD setup

[Wibble12345]

I am pondering over a hard drive setup for my new PC.

Do i use an 80gb IDE for windows with 2 160gb WD AAKS in RAID1
or just 2 320gb AAKS in RAID1

I only have 2 SATA conections on my MOBO

 

[Wibble12345]

I am going to be using my pc mostly for 3d CAD as well as gaimng, so i like the idea of raid1 for the CAD