I don't think the thickness of a motherboard is a direct indicator of quality. Especially comparing to a Gigabyte board- they've been intentionally thickening their boards for that reason for quite a long time, calling it their "Ultra Durable" technology. There are certain brands you just avoid altogether, I think. Chips, BioStar, and for a time MSI, for example. (Somehow, MSI went from low-end scrap dealers to making high-end Gaming stuff though...)
I watched a youtube video from somebody who mostly makes content about older motherboards CPUs, benchmarks them, etc. and I seem to recall coverage on several PC Chips boards, including finding that numerous chips didn't serve any function or had traces that went literally nowhere, including the alleged cache chips.
PC Chips and Technologies also made graphics chipsets, for that they were a little bit better, but still far from perfect. My Toshiba Satellite 440CDX uses a Chips & Technologies 65554 Display Adapter and it has a few quirks.
The first quirk is that it claims to support things like OpenGL, but it doesn't; Or rather, it supports openGL, but doesn't support basic features, most notably texture mapping, nor does it run quickly. Even back then Quake at 8FPS without any textures was something I found unplayable altogether. It's possible this was specific to the implementation on my laptop since from what i can find the same Chips 65554 was used in the Powerbook G3 which didn't advertise or provide OpenGL support at all in that model.