Which ATX form.

[Bazzlad]

My friend bought a barebones system (probably from maplin knowing him) It's a pretty small tower.
He wants me to upgrade it (mobo and proc) I opened it last night and measured it (rough measurement) was 8 1/2 inches by 9 inches - is this likely to be a mini atx, flexatx or an embedded atx?

[jimbouk]

From wikipedia:
FlexATX 9 inches (228.6 mm) 7.5 inches (190.5 mm)
microATX 9.6 inches (243.8 mm) 9.6 inches (243.8 mm)

If it's got 4 expansion slots then it's probably micro atx, pretty standard. See if you can get the mobo make and model number off it to be sure. If you're upgrading then the PSU might need doing as well just to say...