i have a dell dem 8100 and it has a planar mobo it is a 5e692 i need to know if it is an atx or what it is i am going to buy a new case and need to know please help me out i am new to this stuff
It should be an ATX form factor. I have an 8300 and it's a standard ATX mobo. The only thing you need to be careful of is that there isn't anything proprietary like the front panel connections or power supply connections. Sometimes they use things that are not standard.