I was responding to the suggestion that the RAM be compromised while retaining a $100 PC case, which doesn't make good sense to me, but, different people have different priorities.
This PC is going to cost you a good deal, and I would buy the case that YOU really like if money is not a serious barrier. Any case will do, if you like purple, get a purple one.

I personally like some of the fancy aluminium cases with all the whistles and bells but I wouldn't buy one when I need a better video card, you see?
As far as fans go, ANY case is going to cause some heat buildup unless the side covers are off, so....... just get what you like and if it gets hot in summer, just pull a cover off until the weather cools a bit. No hassle at all really.