Can I replace mATX motherboard with ATX without issues for PO7-650 Desktop upgrade?

Hsuan

I am planning to upgrade my current PO7 desktop, and I want to confirm if the original motherboard size is mATX. If I switch to an ATX-sized motherboard, will it cause any size compatibility issues?

[Edited the thread to add model name and issue detail to the title]

billsey

No, the current motherboard carries an ATX form factor of 305 x 272 mm already, so larger than a mATX and in fact slightly larger than the original full ATX form factor. You should be able to fit most ATX motherboards in.

Hsuan

PC Spec: Predator Orion 7000 PO7-650

billsey

No, the current motherboard carries an ATX form factor of 305 x 272 mm already, so larger than a mATX and in fact slightly larger than the original full ATX form factor. You should be able to fit most ATX motherboards in.

Hsuan

https://community.acer.com/en/discussion/comment/1295237#Comment_1295237

I just opened the case and measured the motherboard's size. Should the length be measured up to the white line or the red line in the picture? If it's the white line (measurement should be 244m, mATX), I think the size might not be ATX (305mm).

Hsuan

https://community.acer.com/en/discussion/comment/1295364#Comment_1295364

Or I think I just misunderstood which side of the motherboard is the length and which is the width?

billsey

A replacement motherboard will very likely not have the M.2 slot for a SSD overhanging the edge like the original motherboard does, so you can use the red line for size. The biggest difference between a mATX and ATX is the width that allows for expansion slots. The mATX usually has at most two slots, the ATX can have up to four. Your motherboard has two x16 slots and one 1x slot between the other two. Here's the layout on yours:

Note the slots, #19, 21 and 24 with a gap wide enough for there to have been another between 21 and 24. Next we'll look at the motherboard for a PO3-650:

This is a modified mATX form factor. Note that there are only two slots, #29 & 28, and they don't have that gap between them. This design is modified in that there is that 'diving board' extension out the front to bring ports to the front of the case.