MSI posted a pair of photos on its Facebook page, where it turns out the company was teasing its new X99 board. The board will be known as the X99S Gaming 9 AC, and while no technical specifications have been made available, we are able to see most of what we want to know.
For starters, it looks like the X99S Gaming 9 AC could be an E-ATX motherboard, as it appears a little wider than most standard ATX motherboards. Because we know that X99 motherboards will have the LGA2011-3 socket, we can safely assume that the motherboard has an LGA2011-3 socket, and we can see that wired to this socket are eight DDR4 memory slots. This will allow you to install up to quad-channel memory. PCI-Express expansion is taken care of by five PCI-Express 3.0 x16 slots. We also see an M.2 slot between two of these for SSD expansion. For storage we find two SATA-Express interfaces, along with six SATA ports. If the SATA-Express interfaces are unused you’ll have ten SATA ports at your disposal. Peeking further out of sight we do vaguely see dedicated audio hardware as well.
The rear I/O has eight USB 3.0 ports, along with two USB 2.0 pots. For those who still swear by them, a single PS/2 port is also present. Networking is covered by a Killer NIC along with Wireless AC connectivity. Lastly, we find eight-channel HD audio, accompanied by an optical TOSLINK output.
At this point, this is all we know. It will probably be a few weeks before we know more, including info about pricing and availability. The Haswell-E processors are expected to debut sometime mid-September, and we expect to see motherboards to be officially announced simultaneously.