At long last, AMD's hardware partners have formally introduced a slew of new motherboards based on the company's B450 chipset. Whereas AMD's X470 is aimed at power users and enthusiasts, B450 boards typically target buyers on a budget. Prices vary depending on features, of course, but for the most part B450 motherboards should check in at under $200.
The main thing you give up with B450 versus X470 is multiple GPU support (CrossFireX and SLI). Otherwise, B450 and X470 are overall pretty similar—they have the same number of PCIe Gen3 lanes (16 with Ryzen 7 CPUs), both support overclocking, and both can enable XFR2 Enhanced and Precision Boost Overdrive in second-generation Ryzen CPUs, whereas the previous generation X370 and B350 chipsets lack support for those features.
There are other differences, though mostly minor. B450 has two fewer PCIe Gen 2 lanes (six instead of eight), four fewer USB 3.1 Gen 1 (six instead of 10), and supports two fewer SATA 6Gbps ports (four instead of six).
To kick things off, ASUS introduced half a dozen B450 motherboards. They include the full-size ATX ROG Strix B450-F Gaming ($129.99, Amazon), Prime B450-Plus ($99.99, Newegg), Prime B450M-A/CSM ($89.99, Amazon), and TUF B450-Plus Gaming ($119.99, Amazon), plus two small form factor boards, the mini-ITX ROG Strix B450-I Gaming (not yet priced, Amazon) and micro-ATX TUF B450M-Plus Gaming ($119.99, Amazon).
Gigabyte also fleshed out its motherboard lineup with a bunch of B450 motherboards, and used the opportunity to rebrand its Aorus models "using terminology more familiar to gamers."
Those new motherboards include the full-size B450 Aorus Pro and B450 Aorus Pro WiFi ($119.99, Amazon), along with a couple of micro-ATX boards, the B450 Aorus M ($84.99, Amazon) and the B450M DS3H ($69.99, Newegg), the sole non-Aorus option. The two higher end models sport dual M.2 slots with thermal guards and a hybrid digital PWM, with the latter adding onboard Wi-Fi connectivity.
MSI was the busiest of the bunch, adding nearly a dozen new B450 motherboards to its product stack. It's a varied mix split between full-size ATX and small form factor options.
The full-size options include the B450 Gaming Pro Carbon AC, B450 Gaming Plus, B450 Tomahawk, and B450-A Pro ($89.99, Newegg). For users looking to build a compact system, MSI is offering the B450M Gaming Plus, B450I Gaming Plus AC, B450M Mortar Titanium, B450M Mortar ($99.99, B&H Photo), B450M Bazooka, B450M Pro-VDH, and B450M Pro-M2 ($69.99, Newegg). The Titanium board is arguably the snazziest looking one of the bunch.
We have links and prices to only a few of MSI's offerings, as most of the boards have not shown up in retail yet or are not in stock. They should be soon, though.