Don't know whether it helps - or you've worked this much out for yourself - but it looks like one of those little boards that get attached to a PC case to give you access to ports and sockets in useful places (rather than on the back).
This one has the pink and green sockets, for mic in and headset/speakers respectively, and a couple of USB sockets. Pretty much the only other parts on the board are sockets to run cables (presumably) to the main PC board. These are all handy to have on the front of a case - or, as in the case I'm currently using, on the top. As such, you may find that the manufacturer is a box builder rather than a motherboard maker.
Beyond that, I'm afraid I can't be more specific or more help.