[kijin]

Faster M.2 drives are great, but you know what would be even greater? More M.2 drives.

I wish it was possible to put several M.2 drives in a system and RAID them all up, like you can with SATA drives on any above-average motherboard. Even a single lane of PCIe 5.0 would be more than enough for each of those drives, because each drive won't need to work as hard. Less overheating, more redundancy, and cheaper than getting a small number of super fast high capacity drives. Alas, most mobos only seem to hand out lanes in multiples of 4.

Maybe one day we'll have so many PCIe lanes that we can hand them out like candy to a dozen storage devices and have some left to power a decent GPU. Still, it feels wasteful.

[toast0]

> Alas, most mobos only seem to hand out lanes in multiples of 4.

AFAIK, the cpu lanes can't be broken up beyond x4; it's a limitation of the pci-e root complex. The Promontory 21 chipset that is mainstream for AM5 does two more x4 and four choose sata or pci-e x1. I don't think you can bifurcate those x4s, but you might be able to aggregate two or four of the x1s. And you can daisy chain a second Prom21 chipset to net one more x4 and another 4 x1.

Of course, it's pretty typical for a motherboard to use some of those lanes for onboard network and what nots. Nobody sells a bare minimum board with an x16 slot, two cpu based x4 slots, two chipset x4 slots, and four chipset x1 slots and no onboard perhipherals, only the USB from the cpu and chipset. Or if they do, it's not sold in US stores anyway.

If pci-e switches weren't so expensive, you might see boards with more slots behind a switch (which the chipsets kind of are, but...)

[wpm]

The M.2 form factor isn't that conducive to having lots of them, since they're on the board and need large connectors and physical standoffs. They're also a pain in the ass to install because they lie flat, close to the board, so you're likely to have to remove a bunch of shit to get to them. This is why I've never cared about and mostly hated every "tool-less" M.2 latching mechanism cooked up by the motherboard manufacturers: I already have a screwdriver because I needed to remove my GPU and my ethernet card and the stupid motherboard "armor" to even get at the damn slots.

SATA was a cabling nightmare, sure, but cables let you relocate bulk somewhere else in the case, so you can bunch all the connectors up on the board.

Frankly, given that most advertised M.2 speeds are not sustained or even hit most of the time, I could deal with some slower speeds due to cable length if it meant I could mount my SSDs anywhere but underneath my triple slot GPU.

[nopesayer]

Asus m.2 add in risers would like a word ala Gene X670E.

[kvemkon]

> I could deal with some slower speeds due to cable length

Observing server mainboards reveals many PCIe 5.0 connectors for cables to attach PCIe-SSDs looking similar to SATA ones.

[jononor]

Agree that M.2 is fiddly. PCIE cards with M.2 sockets are nice nice for desktops and servers, then one can just unplug it to do operations.

[Aurornis]

There are add-in cards with PCIe switch chips that will let you put a large number of drives into a single PCIe slot.

[Gracana]

Including ones that have controllers, if your motherboard doesn't have enough lanes or it doesn't support bifurcation. I have a Rocket 7608A, which gives you 8 M.2 slots in a PCIe 5.0 x16 card: https://www.highpoint-tech.com/nvme-raid-aic/gen5/rocket-760...