AMD announced six chipsets for Ryzen based on AM4: X370, B350, A320 and the mini ITX X300, B300 and A300 with the X370 and B350 already in pre-order and availability next week. 

The lads over at ComputerBase compiled an overview chart to demo the chipsets differences in a better to understand manner features wise. First off, it looks like only the X370 chipset is going to support SLI. That means the B350 would not support SLI (but does support Crossfire). THis information has been confirmed. We are not sure why but Nvidia might still be licensing SLI functionality and thus SLI supports adds a charge per sold motherboard. The B350 series is a more budget aimed one so the choice makes sense.

You'll notice there are 20 PCIe 3.0 lanes pulled from the Ryzen processor. Ryzen has 24 of them yet 4 are being used to interface with the chipset. Then depending on the chipset used it adds gen 2.0 PCIe lanes through the chipset. The X370 will add 8 lanes, B350 6 lanes and onwards. Have a peek at the chart for more details.

I / O interfaces of the chipsets and processors

 
Each chipset will add USB ports, but the Ryzen processor also offers four native USB 3.0 ports. There is support for RAID 0/1/10 configurations as well as Overclocking support on the X370, B350 and X300 chipset. Obviously the motherboard partners can add 3rd party chips to increase USB 3.0 and so on. The four PCIe 3.0 links for X300 / B300 / A300 seem to be a bit odd, we'll try and confirm that soon.

AMD X370 B350 A320 X300 and B300 / A300 Compared - Only SLI for X370