EggXpert

I can't believe I don't know this and can't find the answer with a Google search, but will a regular ATX motherboard fit in a mid tower ATX case, or do I need to find a micro-ATX motherboard? 

I'm looking at some relatively inexpensive Lian-Li cases because I've heard good things about them, but they all seem to be mid-tower ATX cases, and I was planning on buying a full ATX form motherboard.  I'm planning on a gaming rig; not very very top of the line but with a lot of power, two graphics cards, core i7, and at least 4 gigs of ram, so it would need fairly good airflow too, which I guess might be a problem with a smaller case?

The person I'm building it for prefers something slightly smaller than a full size but isn't really stuck on it; we don't need more than one dvd drive and two hds to fit in the case, so if the difference is in the drive bays, that isn't much of a concern. 

No worries.  Yes, a Mid-ATX form factor will support a regular ATX sized motherboard.

I am personally a fan of the Mid-ATX case.  As long as you tuck the wires away well enough, airflow shouldn't be too much of a problem.  LianLi is well known for how well their cases ventilate and how stylish they can be, so I think you're making a good choice there if the person you are building for can afford it.

That said, because of the length of my ASUS Radeon HD 4870x2 (an ATI card), I was forced to ditch my Mid-ATX case in favor of a full ATX case because my graphics card stuck out too far.  If you are looking for a suggestion for a good full ATX case, check out the Cooler Master HAF 932.  This thing is amazing in terms of cooling and the sheer amount of options for mounting fans/watercooling. 

A mid-tower case will fit an ATX mobo fine, but you have to consider all your components.   Mid-tower cases are often unable to accommodate tower-style 120mm CPU coolers  (My ZeroTherm FZ120 barely fits in my RC-690 full tower), some high end video cards (i.e. ATI 5870/ Nvidia GTX295)  might have problems fitting in, and drive cage does not fit as many hard drives.   Of course, if you only have 1-2 HDs, a shorter video card, and bump down to a 92mm cooler, you should have no problem.   And yeah, Lian-Li LanCool cases  are very nice.

Thank you both for the very helpful responses!  You've given me great advice. 

I just bought an Antec 900 case and it is classified as a Mid Tower, but it is big. Holds full ATX board and has 2 huge fans on front, top and back. I got my overclocked AMD dual core at 3GHZ from 2.6GHZ and she is sitting at 33 degrees celcius idle. I got a ThermalTake V1 in there also. Lots of space. I am going to buy another one of these cases.