There is an important distinction between who supplied you the motherboard ie the packaging on the mobo's box or the name on the PC's front, and who manufactured the motherboard.

 This distinction is only absoloutely vital if you are upgrading the BIOS.

 There are a couple of techniques for finding the mobo's manufacturer, the easiest (IMHO) is to find the FCC ID on your mobo, then look it up here:

http://www.fcc.gov/oet/fccid/help.html

Can I state that if you have never 'flashed' a BIOS before to hang back before you do this and read up as much as possible on the subject.