Agree w/ CCats! mATX case has room for only 4 add-on card slots while an ATX mobo has seven card slots. Typical mATX mobo is only 9-10" wide... But there might be a rare possibility you just have to judge how much room there looks to be between the last card slot and the side or bottom of the case - needs to have at least 3 extra inches. There are some fairly compact ATX cases out there but you have to search for them. If I recall, Suntek made one (STK9311 - 15x8.6x15"). Here's a link to their US page:
Linkage . The STK9511 is similar but has a top handle and optional front USB (have to install your own port panel in the 9311 - use a 3.5 or 5" drive bay) - convenient for LAN Party box. If I recall correctly, the 9311 has storage for a few frequently used CDs on top (used to sell it at CompUSA here so I've actually seen the 9311 in the past). Neither comes with a PSU unless added by your reseller.
. Note the tight fit (click on some of the links near the bottom of the pages to see more pix) - may have to use low profile memory, compact HSF (e.g. Thermal Integration V77L), use the new short-chassis optical drives, etc. The Suntek cases are also very hard to find here in the states. And you may have to think 'outside the box' (literally) for cooling options.. But it is a very clever design - I particularly like the black/white color scheme (click on the little color dots to see the various schemes) - the black is actually smoked translucent.
.bh.
Where's the :sun: ?