I am looking for information on M.2 bandwidth for gen 4 nvme. I’m wondering how M.2 carries PCI lanes or PCIE packets. What is the new revision, for gen 4 nvme drives, called. I can’t seem to find any information online about M.2 bandwidth: for the latest generational progression (nvme 4.0). I’ve found that current laptop M.2’s only carry a max PCI 3.0 4x.
Also I’m wondering for eGPU’s. I have found m.2 to physical 16x pcie 3.0 slot adapter and I’m assuming 4.0 hardware will show up in due time. I would like to use a future Laptops that two has M.2s, one for a eGPU and the other for an NVME. I have been getting into AI and having a laptop I can work on with the largest GPU memory would help my render times. Information on bandwidth limitations for ai work flow is limited when looking for information related to thunder bolt 3. If I can assume that the latest M.2 supports pci 4.0 at 4x then having 64Gbs bidirectional would be much better than Thunderbolt3 shared 40Gbs.
P.S.
I know a desktop would be better for this type of work but Im planning on upgrading my laptop anyways and I’m using AI to archive and improve Family photos, home videos and things like that. I’m a hobbyist. My current laptop has a i7 7700hq and a 1060 it takes 12 hours to render a 30min clip from 480 to 1080p so any computer I get will be better, but I like the idea of future proofing. I have a 40Gb/s TB3 port but it wasn’t the connector we needed its the connector we deserved. Also rather spend the $300+ an enclosure costs on my new laptop.
You seem to want a future laptop that can put a GPU into a M.2 slot? That is just not going to happen. A GPU is way too big for that.
Or some kind of Frankenstein thing with a ribbon cable coming out of a laptop case to a GPU, what, sitting on your desk? How’s it going to get power?
TB3 is becoming USB4 in the near future but it won’t be PCIe4 speeds. Even the short cables that TB3 supports are difficult to get good signal quality on. PCIe4 is even worse. External USB4 GPUs are not likely to get higher speed connectors for a while. When they do, it may be fiber optic.
M.2, like U.2 is basically a form factor that uses a certain kind of physical connector.
These connections types can have different and generally incompatible transfer protocols running over them, such as NVMe, SAS, SATA.
An M.2 NVMe drive for example will not work in a M.2 SATA slot.
For NVMe drives, if the drive or the slot are not specifically mentioned to support Gen4 PCIe, then you can assume they are Gen3. Refer to your motherboards specifications to see what the slots support. They should have a block diagram: Example
Gen4 drives are backwards compatible, and will automatically run at Gen3 speeds in a Gen3 slot, and vise versa.
If your motherboard supports pcie bifurcation in the bios (turning a 16x into 4x4x4x4) then you can use one of these cards, otherwise it will only see a single drive.
Be aware that many non TR/EPYC motherboards may have a 16x pcie slot that is actually only 8x or even 4x electrically, additionally they may be a mix of Gen4 and Gen3, as well as having slots be disable in certain conditions or have bandwidth contention due to actual being fake pcie lanes switched by the chipset.
4x.
M.2 M-key is physical PCIE4x width. It just uses smaller pads/traces. It’s the same for PCIE1.0, 2.0, 3.0, 4.0, and will presumably be the same for PCIE5.0, barring a physical change to the connection.
Provided you can power the GPU, in theory, it should work to just connect via adapter to nvme. However, it will be physical 4x speed. I can’t imagine that’s a good idea on a laptop, though, and there may be issues with rated power delivery or available power sources, as those can be different depending on the PCIE revision and port type.
Really I just needed more information about the connector. Does it carry Pcie packets like TB3 or native Pcie lanes. This seemed to be awnserd by other commenters. However, I was looking for links to be able to do more research myself.
Here are two links one for the current hardware adapter that would need to be released in a pcie gen 4 version. The second is an equivalent benchmark to show performance on a “pci 4.0 4x slot”.
Yes I would be doing a frankenstein build. As I can set up for a long render time at my desk with a desktop power supply and can unhook everything when the Job is done.
The new zen 3 mobile chips should come with two 4x m.2s and the current top end Intel laptops do but use pcie 3.0 not 4.0
The short comings of Tb3 and TB4 is why I’m considering this option.
m.2 nvme can be passively adapted to pci-e.
There are additional caveats with power delivery and bios settings. And some m.2 slots are only sata so they won’t work but for the most part the first statement is true.