Although based on two different chipsets, both the ROG Strix X370-I Gaming and the ROG Strix B350-I Gaming offer pretty much the same features and specifications, mostly due to the 17x17cm mini-ITX form-factor. In general, there isn't much difference between X370 and B350 to start with, except for a higher number of USB 3.1 Gen1 ports, SATA ports and an ability to support dual graphics cards in Crossfire, which is not happening on a mini-ITX motherboard.

According to Asus' own specifications for the ROG Strix X370-I Gaming and the ROG Strix B350-I Gaming, both feature support for AMD Ryzen and 7th generation A-series chips, Digi+ VRM, two DIMM slots with support for up to 32GB of DDR4-3600 memory, one Asus SafeSlot PCI-Express 3.0 x16 reinforced slot, four SATA 6Gbps ports, two M.2 NVMe slots (one on the backside of the board), two USB 3.1 Gen and four USB 3.1 Gen1 ports, Intel I211-AT Gigabit LAN, integrated dual-band 802.11ac WiFi with MU-MIMO and Bluetooth as well as Supreme FX 8-channel HD audio with S1120A codec.

Due to the limited PCB "estate", Asus had to combine audio and one M.2 slot on a unique riser card which also features a PCH and M.2 heatsink.

Both motherboards also come with Asus' own 5-way optimization with TPU, EPU, Fan Xpert 4, Digi+ Power Control and Turbo App, multiple temperature sensors on board, and Asus' Aura Sync RGB with dedicated RGB headers.

Unfortunately, Asus did not reveal any details regarding the availability date or the price but these two small motherboards will most likely cost a pretty penny considering a number of features that Asus crammed on such a small PCB.