Inside Lian Li’s PC-B12
Naturally-colored aluminum panels brighten the PC-B12’s interior. We like this because unpainted interiors are easier for us to service, even though many readers prefer all surfaces to look the same. In this case, function supersedes form, and that's fine because there aren't any windows on the PC-B12, so the insides are hidden behind painted side panels.
There’s barely enough space behind the PC-B12’s motherboard tray for routing cables, and almost none for hiding excess cable length. Due to the lackluster cable management, it’s probably best that this case isn’t offered with a side-panel window (which would have just made it noisier anyway).
As many companies are known to do, Lian Li's PC-B12 likely shares some of its parts with other models. This would explain the filler panel covering a large portion of the front face that looks as though it was originally cut for fan mounts. The new fan mounts are about an inch behind the face, leaving enough room for the intake duct that draws air through a slot on the bottom.
The extended fan mount is secured by two screws on the front side of the chassis and sliding tabs on the back. The drive cage is held in place the same way, though a third screw connects it to a bracket on the motherboard tray.
Your platform of choice's maximum width is restricted by a bracket on the PC-B12's motherboard tray, meaning this case only supports boards falling exactly within the ATX specification. While that bracket is removable, the drive cage that it connects to would still restrict the installation of oversized motherboards.