PSU and Mobo fitting

Looking at this case for my new rig:
http://www.vadim.co.uk/Components/Cases/Performers/Chenbro+Gaming+Bomb+Silver+with+Window+(No+PSU)

and trying to see if this will fit in:
http://www.vadim.co.uk/Components/PSUs/FSP+400W+60GLN+OEM+PSU+(environment+friendly)

I’m guessing this line in the case description:

M/B Form Factor ATX (up to 12” x 10.5”)
Is the size of the mothor board it can fit?
If so I’m looking to put a Gigabyte Skt939 mobo in there

Probably a http://www.vadim.co.uk/Components/Motherboards/AMD+939/Gigabyte+GA-K8N+Ultra-9+S939

from what I can see it will fit seeing as it’s form factor is ATX as well…

any help or feedback?