Just for let you know, I found this here http://www.angxunmb.com/web/index.php?topclassid=16&classid=64&id=307&lanstr=en&wap=1
Manufacturer seems to be Shenzhen Angxun Technology. I renamed the manufacturer of the category. The board was also available as Machinist and with C612 SB. There are 3 revisions of the board. However I doubt that this matters anyway, as it seems that CPU-Z cant read the real used chip. On the linked page, the board should have HM55 SB but CPU-Z reads QM57. Either this, or they simply used what they had in stock.