Sheesh, that changes so fast, I can't give you actual components right now. Maybe if I got some time tomorrow I could have a talk with the guy in ye shoppe I trust to give reasonable answers to my questions.
But something that is kinda indepent and universally true:
The mobo might be the backbone of the system, but hardware evolves quickly and sometimes has great fluctuations in price. I see the case more backboney, you can carry that over in between major system rebuilds. Unless you keep the old box as backup system.
Anyway. Get something decently purdy, I like to pick black, and try not to get too small. Especially girlfriends (sorry for sexism here) seem to think about the room and the fengshui more than the airflow inside the case, and so they want a small case they can fit in neatly between some drawers. Teh Horror. So, prefer to go big, it keeps the cost down with the other components and also helps with cleaning, which in turn, improves stability (Heat is bad, remember
) As I said, I got my case for 30, and it's pretty dang perfect. In the front there are several slots for drives, and the lower half of them sort of works as a dust filter. Special inlays you can clean and stuff. Behind those I put a 5 buck fan, same diameter as the whole front, that sucks in the air and blows it through the whole case. The fan got blue leds, same as the case, all a coincidence, but it makes the thing look sort of pimpy, which is funny, considering the price.
I tucked the cables away neatly, so they dont get heated up and they dont block the airflow. The psu sucks the warmish air through and out on the back. I know that isnt exactly ideal, but another 2-3 buck fan below the psu, pointing out of the back (so the airflow really gets sucked through the whole case) would change that. In my case it aint necessary, because there is enough room and it just works out.
So if you're looking at 1 vidcard, 1 HD and 1 DVD thingy and maybe 1 extra card for whatever, you have good chances building the thing in a way it's easy to keep cool. Because you then can OC the thing cheaply. And with a lot of CPUs that isnt a biggie at all. It's like they are built to run faster, they just really really run in the safety zone. for people that live in the 3rd circle of hell, you know, like for tax collector or banker PCs.
If you cram the box full of stuff, you might need to spend more on the case, because it will be harder to cool, but I dont expect that, considering your first post.