You remember way back about 24 hours ago when we reported on that ITX Ryzen motherboard that Asus was teasing? As it turns out, the company actually has a pair of new motherboards, and we've got the full details on them now. The two boards are the ROG Strix X370-I Gaming and the ROG Strix B350-I Gaming. As you no doubt expect, both models fit the mini-ITX form factor and have AM4 sockets.
In our comments, gerbil tsk pointed out that the AMD X370 chipset doesn't offer a lot over the B350 chipset for an ITX motherboard. His observation was markedly astute, as these two motherboards appear to be completely identical. That means both models come with a pair of DDR4 DIMM slots capable of running their memory at up to 3600 MT/s, along with a single PCIe 3.0 x4 M.2 socket, a PCIe 2.0 x4 M.2 socket, and four SATA ports.
Perhaps the most interesting feature of these boards is that their audio hardware actually comes on a daughterboard suspended above the PCB. That daughterboard also holds the aforementioned PCIe 3.0-capable M.2 socket. The whole thing then gets covered by an aluminum plate bearing an RGB LED-illuminated ROG logo. Given that Asus refers to the cover as a "heatsink" we'd have liked to see some fins on it, but in our experience M.2 SSDs don't really need that much cooling anyway.
The audio codec on hand itself is the Realtek S1220A on both boards. The networking hardware is all provided by Intel, and consists of the usual Gigabit Ethernet and 2x2 802.11ac Wi-Fi. Whichever model you choose, you'll have four USB 3.0 ports and two USB 3.1 Gen 2 ports on the back panel, as well as another two USB 3.0 ports and a pair of USB 2.0 ports via internal headers.
Jeff correctly identified the onboard connectors yesterday, although one of the RGB LED headers is Aura Sync-addressable. There's also a dedicated connector for water-cooling pumps like on the majority of Asus' finer boards, as well as a thermal probe header. Given all that clearance around the CPU socket and the generous allocation of power phases, these boards might be able to take Ryzen CPUs to their limits. Asus says the ROG Strix X370-I Gaming and B350-I Gaming will be available late this month.