Weird sized motherboard?

[KainArkanos]

So I have a 2600k system I was trying to revitalize with a new motherboard due to the failure of my previous Gigabyte z68-ud3h-b3, and grabbed an Asrock z77 pro 3 to replace it, but upon receiving it I noticed the motherboard is...way smaller in width than the z68, which was a standard ATX board and I've never seen a board that is slimmer in width but the same length as standard ATX before, what the heck is this board?

 

[Darkbreeze]

It is ATX form factor. Perhaps your older board was the one different.

ASRock Z77 Pro3

- ATX Form Factor: 12.0-in x 7.6-in, 30.5 cm x 19.3 cm
- All Solid Capacitor design

Z68-ud3h-b3
ATX Form Factor; 30.5cm x 24.4cm

The form factor really doesn't have to be an exact size. It simply needs to be WITHIN a specific range AND must conform to the mounting holes being in an exact pattern and size. There are motherboards out there with weird partial L shapes, and so long as they will fit into an ATX case and the standoffs match up, they will still be ATX.

 

[KainArkanos]

Actually, it misses 3 of the 9 standard mounting standoffs for actual standard sized ATX motherboards because it is so much smaller in width than an actual standard sized ATX board. I've owned several computers at this point, all leading back to the 90s, and every one that was a standard ATX, not extended ATX, always used 9, pretty much equally spaced mounting points. This one only has 7 mounting points as it is not wide enough to reach the last 3 at the end designed for standard ATX, and instead has two mounting points very close to each other near the PCIE ports, as designated by Flex-ATX boards, which are actually smaller than even this board.

 

[Darkbreeze]

You're right, it does only have 7. That's pretty weird, but not entirely surprising. A lot of low end boards, and that was definitely not a higher end example of a Z series board, do weird things or leave off features found on the rest of the chipset.

Looking around it seems that ASRock had several "slim" ATX form factor boards, the Extreme3 being another with only 7. Might have been an ASRock thing. Never seen that on any other brand of motherboard when it declares itself as ATX form factor.