We've all been there, right? You want to add another SSD to your system, but all your M.2 sockets are full. You could get a SATA SSD, but that's not going to satisfy your need for speed. No, you definitely
need more NVMe storage, and that means you're going to have to get a PCIe-to-M.2 adapter. If that's the case anyway, why settle for one drive when you could have four?
The answer to this question is, of course, because you don't have an available PCIe x16 slot. You might, if you're satisfied with
the integrated graphics of your system, but we reckon that most folks building desktops for the kind of work that could actually require this much solid-state storage will want to have a graphics card, too.
This product isn't exactly "novel" so much as it is "updated." ASUS and others have been selling "Hyper M.2 x16" cards for
a few generations now, and the latest model is made for PCIe 5.0 SSDs. On the card, you get four M.2 slots with thermal pads on both sides, a squirrel cage fan to keep them cool, and a six-pin PCIe power connector to feed the beast. Around the back, there are vents and four activity LEDs for the SSDs.
This thing seems pretty slick, so what's the catch? Well, as we mentioned above, this card requires a PCIe x16 slot. You might think that you could be clever and install it in an x1 or x4 slot, and it's likely that it will work—but only for one of the four M.2 SSDs. That's because there's
no PCIe switch on this card; each M.2 socket is wired up to four lanes on the physical x16 connector.
That means that to properly make use of this card, you'll need a PCIe slot that is x16 both physically and electrically, and you'll also need your motherboard to have support for four-way PCIe bifurcation. That's not uncommon on higher-end desktop boards, but ultimately the place where you'll want to use a card like this is probably going to be in a proper "high-end desktop"—that is to say,
a Threadripper or Xeon workstation that can actually provide the necessary PCIe expansion without sacrificing its graphics card.
ASUS trumpets the Hyper M.2 x16 Gen5 card's RAID capabilities. It doesn't actually have a RAID controller onboard, but you could easily set up firmware or software RAID across the four NVMe drives, or even more if you have additional SSDs connected to your CPU. ASUS claims that you could achieve a peak performance of 512Gbps, or about 64 gigabytes/second; in practice we'd expect that to top out around 50 GB/sec or less. Still incredible storage performance, of course.
The advantage of not including an expensive PCIe switch IC is that the card can be relatively affordable. ASUS says its
Hyper M.2 x16 Gen5 card will run you $79.99 when it becomes available sometime after next week.