Is there a game-changing M.2 design?
Recently, the proliferation of M.2 socket can be seen on many ultrabooks and tablets, as the tiny dimension is quite suitable for compact devices. Could it be possible to utilize this interface on desktop motherboards? Moreover, is there a game-changing M.2 design to push the speed even further?
What is M.2?
M.2, formerly called “Next Generation Form Factor” (NGFF), is the latest I/O solution of replacing Mini-SATA (abbreviated as mSATA) and breaking through the speed limit of the current SATA3 6Gb/s. Leading by Intel Inc., M.2 technology is based on the PCI Express interface and also compatible with the SATA interface. Dimension-wise, the line-up of the commercially available M.2 expansion cards is 22mm wide, with varying lengths of 30, 42, 60, 80 and 110mm.
M.2 vs. mSATA
mSATA is another alternative I/O solution, yet it is basically a SATA interface with a different connector (like micro-USB to USB), so the I/O speed is almost the same.
On the other hand, the theoretical speed of a PCIe interface M.2 device is based on PCI Express bandwidth it uses from the onboard chipset. For example, a PCIe x2 M.2 device is able to reach up to 10Gb/s.
As the I/O speed of traditional HDDs has been the bottleneck of Desktop PC performance for years, M.2 appears to be a very ideal solution. Compared with mSATA and SATA interface, M.2 has a smaller and more flexible physical specification; therefore it is more suitable for solid-state storage applications in general.
On a regular motherboard design, the signal route starts from the M.2 device, goes through the onboard chipset, and finally reaches CPU.
However, the bandwidth of the onboard chipset is limited to either PCIe x2 or SATA3 6Gb/s.
Apparently, if we want to utilize more bandwidth for M.2 devices to get even faster speed, directly connect to CPU may be a good idea.Ultra M.2
By connecting the M.2 interface to CPU directly, Ultra M.2 design lowers the latency and pushes the I/O speed to a new level.
The theoretical speed of PCIe x4 Ultra M.2 is 32Gb/s, 6X faster than PCIe x1 M.2 socket, 3X faster than PCIe x2 M.2 socket.
We tested the read speed of Samsung XP941 PCIe x4 M.2 SSD on Ultra M.2 socket.
It reached 1.16GB/s, 46% faster than PCIe x2 M.2 socket.
Benefited from the direct linkage between Ultra M.2 interface and CPU, its read speed is 8.8% faster than normal M.2 socket. As we can see, the lower latency of Ultra M.2 design does matter.
M.2 is the key component to break the I/O performance barrier on current desktop PC.
Nevertheless, its speed is still limited to the bandwidth of the onboard chipset (PCIe x2 or SATA3 6Gb/s).
As hardware enthusiasts, we are looking forward to see Ultra M.2, the cutting edge design on the upcoming ASRock Extreme6 motherboards that links the M.2 interface to CPU with PCIe x4 bandwidth directly.
In our opinion, the innovative Ultra M.2 is definitely going to break through the I/O speed limit and change the game.