As of 2013, following are the top 3 manufacturers of desktop computer motherboards.
Sale Rank: 1 (Q1 2013 – Sold 5.0 million motherboards.)
ASUSTeK Computer Inc. is usually referred to as Asus. They are also trading under Asus brand name.
Asus is a Taiwanese multinational computer hardware and electronics company headquartered in Beitou District, Taipei, Taiwan.
Asus supports two main CPU manufacturers: Intel & AMD, and currently supports variety of popular sockets: Socket 1150; Socket 2011; Socket 1366; Socket 1156; Socket 1155; AMD AM3+; AMD AM3; AMD Socket FM1; AMD Socket FM2; AMD Socket FM2+; Intel CPU on Board; AMD CPU on Board.
They also support the latest technology, such as PCIe 3.0, SATA 6Gb/s; USB 3.0; M.2(NGFF) and NFC EXPRESS.
Sale Rank: 2 (Q1 2013 – Sold 4.9 million motherboards.)
Gigabyte Technology Co., Ltd. is a Taiwan based manufacturer of computer hardware (mainly motherboards). The company is publicly held and traded on the Taiwan Stock Exchange.
Gigabyte estimates its shipping of motherboards in 2013 to be close to 21 million units, which is the company’s 28-year history record.
Gigabyte, same as Asus supports mainly two main CPU manufacturers: Intel & AMD and also popular sockets, but they also concentrate on making motherboard integrated (and standalone) graphics cards built around the AMD and NVIDIA GPUs.
Intel Corporation (United States)
Intel was founded in Mountain View, California in 1968, starting manufacturing motherboards in 1990. While never a huge player on the motherboard market, they sold a considerable numbers of motherboards though OEM PC channels.
Motherboard manufacturing concentrates mainly on support of their own Intel CPU products.
Due to declining sales, in 2013 Intel revealed plans to discontinue manufacturing of desktop motherboards and closing its mainboard division in 2016/17. Reason is mainly due to Asus and Gigabyte capturing most of the motherboard business.