As reported a few days earlier, ASRock's new Ultra M.2 socket offers increased bandwidth by changing the layout of its bus lanes to bypass the Z97 PCH and connects the PCIe M.2 SSD directly to the CPU to reduce latency. Tapping on the CPU's speedier PCIe 3.0 connection and using a wider x4 interface, the theoretical speed of Ultra M.2 socket is 32Gb/s, six times faster than PCIe x1 M.2 (5Gb/s), and three times faster than PCIe x2 M.2 (10Gb/s). For now, the new Ultra M.2 socket is only featured on the ASRock Z97 Extreme6 motherboard. This board is part of the new slew of Intel series 9 offerings from ASRock.
For best utilization of the new Ultra M.2 socket, you'll need a M.2 form factor SSD that supports speedier transfers. Currently, the M.2 form factor officially supports PCIe 2.0 x2 interface. The only M.2. form factor SSD that will exceed this specification is the Samsung XP941 PCIe M.2 SSD which apparently operates on a draft specification of a PCIe 2.0 x4 interface. Since the ASRock motherboard's Ultra M.2 socket uses a speedier PCIe 3.0 x4 interface, enthusiasts can benefit from faster and better PCIe M.2 SSD implementations in the future. We witnessed the Ultra M.2's capability at a local ASRock motherboard launch seminar that utilized this particular Samsung M.2 SSD for demo:-
While it will take time before you can get your hands on speedier PCIe M.2 form factor SSDs such as the Samsung XP941, ASRock meanwhile assures you that the speedier and lower latency Ultra M.2 interface boosts transfer speeds on existing M.2. SSDs by up to 8%.
There's one catch to Ultra M.2 socket though - you'll have to forgo PCIe 3.0 x16 transfer rates on your PEG slot and settle for x8 transfer speeds. As pointed out earlier, the Ultra M.2 socket feeds off the PCIe 3.0 lanes supplied by the CPU and this directly impacts the throughput available for your PEG slots. Fortunately, if you plan to run a single GPU setup, the decrease in PCIe throughput is almost negligible. After all, most multi-GPU configurations already operate on PCIe x8 or even x4 transfer rates and there isn't much of a drawback. As such, it's a smart design trade off which ASRock is capitalizing to differentiate its offerings.
Stay tuned to a review in the near future where we further test the motherboard and the Ultra M.2 proposition.