atx compatible case

[doom3fan]

Well i ran into a problem building a pc for my grandparents i am thinking of Re purposing my old rig for them but my old rig has a full atx motherboard and i am having trouble finding a case small enough to fit at there computer desk there desk has like a 14-16 inc or 355.6mm to 406.4mm inlet for there computer that is depth and i don't want to get them a computer case that is going to stick out but im having trouble finding a ATX case with less then 18-19 inc 457.2mm- 482.6mm + depth the with really dosn't matter Was looking for suggestions and i don't want to spend much more then $80 on a computer case

 

[Chayan4400]

Well i ran into a problem building a pc for my grandparents i am thinking of Re purposing my old rig for them but my old rig has a full atx motherboard and i am having trouble finding a case small enough to fit at there computer desk there desk has like a 14-16 inc or 355.6mm to 406.4mm inlet for there computer that is depth and i don't want to get them a computer case that is going to stick out but im having trouble finding a ATX case with less then 18-19 inc 457.2mm- 482.6mm + depth the with really dosn't matter Was looking for suggestions and i don't want to spend much more then $80 on a computer case

Well...

ATX motherboard is 12"x9.6"
ATX power supply is 5.5"
Optical drive is ~7"
Picked a random good video card (GTX 770 2 fan) length was 10.5" (3 fan is 11.5")

Finding a full sized atx case for those dimensions is going to be rough. Keep in mind that you still need to add depth due to fans front and rear (about 1 inch each) as well as for the structural frame front and rear and any sort of face plate. Even disregarding the video card if you take your 9.6 inch motherboard and add in 2 inches for fans and then another inch and a half for structure you still have 12.5 inches and that provides zero room inside for shifting things around which isn't going to happen. Add another 4 inches and you're up around 17 inch mark.

Most OEMs use mATX boards, and don't include support for enthusiast GPUs which is why most computer desks have small compartments for the computer. For custom case builders though, bigger is better as people typically want as much space as possible for their components, which is why it will be very hard if not impossible to find a case that supports ATX motherboards that fits your needs.

EDIT: This is the smallest I could find: Click here.

It still may not fit as it is quite wide, so could you post exact measurements of the length, width and height of the compartment?

EDIT 2: Here are a few others:

Cooler Master N400: Click here.
Antec NSK 4482B: Click here.
Corsair Carbide Series 100R: Click here.