http://www.pcgamer.com/this-mini-itx-gaming-motherboard-from-asrock-is-120-after-rebate/

If you are looking to build a small form factor gaming PC that packs a punch, you might consider ASRock's Fatal1ty X370 Gaming-ITX/AC motherboard. It's on sale at Newegg this week for $140, with a $20 mail-in-rebate available to bring the price down to $120.

As the model name implies, this is based on AMD's X370 chipset for Ryzen. Combined with the recent price drops on Ryzen processors, you can piece together a pint-sized powerhouse on a modest budget. At present, Ryzen processors range in cost from around $110 (Ryzen 3 1200) to $400 (Ryzen 7 1800X), with several options in between. A decent option to pair with this board is a Ryzen 5 1600X, a 6-core/12-thread CPU that can be bought for $220 after using promo code EMCBRCR24.