. . . I was looking at a Noctua NH-U9B SE2 as the fix for this. Comes in just under 5" tall. Any other ideas on this?
Next and most difficult issue is the 5770.
1 - that NH-u9b is an AWESOME cooler. It performs Extremely well - i've had it, hell - i still have it and will be using it on my new HTPC build. You won't be dissapointed.
2 - Vid card - is this computer setup already? I would try 'as is' for now and see what your temps are like and what the noise is like.
I have my cards set at 0% fan speed through afterburner until they hit 50 degrees. Then they ramp up. Saying that - i've got a ton of airflow through my case and they don't hit 50 until I'm gaming.
3 - FAN CONTROLLER. Us the biggest fans possible. I would even go as far as cutting up your rig / case to get a bigger fan in there if you find heat to be an issue. It's easy, and it can look amazing with the nice grills available now.
I'd get the heatsink for your cpu - get the machine running and then worry about the vid card / other issues if there are issues. Whether be noise, Heat - whatever.