I would change the motherboard to a Z68 rather than the H61, I would look at getting a better brand of PSU than a Powercool. Case is pretty naff in my opinion. I personally would not bother with a separate sound card, but that is your choice. Your motherboard is m-ATX and can only handle one card there is no SLI so you cannot put to 6850's in that board.
Have a look here,Page 2. There is a few set ups you might like to look at.