I've listed my current build idea below for reference. Right now I'm leaning toward the NZXT case right now since it is easily the cheapest and its design appeals to me the most. I am slightly concerned about mounting the PSU at the top though. I've never built a PC before so I don't know if this should be a concern. Anyways, if you have an input on the matter I would be glad to hear it or if you've had any experience with any of the cases I listed that would be great.
The Antec Nine Hundred pc case is one of the most popular, if not the most popular case with gamers. I have not seen actual sales figures but I think it is Antec's all time best seller. Ventilation, air flow, and cooling are excellent.
The Coolermaster Storm Scout is a fairly new addition in Coolermaster's line of cases and it too is becoming quite popular with gamers. Ventilation, air flow, and cooling are also excellent.
Sometimes it boils down to personal preference. Buy the one you like.
I does not matter whether a power supply is installed in the top of the case or the bottom of the case. The theory with the bottom mounted psu is that it helps the case maintain stability and keeps the case from tipping over.
Your list of components is missing a cpu heatsink. Here is a link to a web site with lots of information about heatsinks that you might find interesting:
One thing to consider is the NZXT's 10$ shipping fee, that bumps it up into the Storm Scout's price range before MIR. They're all roughly the same size, the NZXT has more depth but is shorter than the other two. Nothing really to worry about with the top mounted PSU, although it may make the cablework slightly more unruly.
You listed three different tiers of cases. The NZXT is the low end, the Scout is in the middle, and the 900 is in the top end. So you aren't really comparing apples to apples.
My suggestion, given the fact that you want to run 2 crossfire cards in there is to go with the best cooling case you can afford. Of the three you listed, the Antec is the best choice, but you might also want to consider any of these:
Finally, I just bought the same PSU as you have above --- the Antec EarthWatts EA750. I wasn't that happy with it --- I had been hoping that the cables were long enough that I could route them behind the backplace on the HAF922 case I got, but there were a few inches short. The number of non-modular cables included was more than I needed. As a suggestion, I would point you to
In all honesty all your selections are good for a low end machine my suggestion is to go with a full tower case.Main reasons being airflow rduced wire clutter and space for expandability. you can get the haf 932 for 150ish and is a very popular case if you want an excellent case thermaltakes spedo is well just great amazing airflow lots of fans and bottom psu. The reason for cases having a bottom mounted psu is air intake when placed at the top it sucks air from inside your pc and seeing as heat rises it tends to be the hottest air in your case bottom mounted psu's suck air from the bottom wich usually has venting and allows for exhaust fans to be placed on the top thus expelling all your hot air much more efficiently
If you are looking at the antec 300, look at the Antec 300 illusion. Its the 300 with two front 120mm blue led fans to push cold air from the front (like the 900 has). Lots better airflow for $15 more (less than buying the fans yourself).
Now that I have an antec 900, I will never get a case without at least one front fan to create good front -> back airflow.
Check out the Coolermaster RC-690. Places for 8 fans, deep enough for 120mm tower coolers, and bottom-mounted PSU which I think is better for cable management, plus the previously-mentioned stability. I also like the top-mounted ports, which are very convenient unless your PC sits up on your desk. It is only $70 right now: http://www.newegg.com/Product/Product.aspx?Item=N82E168...