Lenovo demonstrates NVMe M.2 alternative to Thunderbolt for high-end external desktop GPUs on AMD-based notebooks

[Redaktion]

AMD's support for USB4 and Thunderbolt is scheduled to arrive in early 2022, and, until then, laptop OEMs are trying out alternatives. One solution would be to implement a new type of connector, like Asus has done on its new ROG Flow X13 laptops. Lenovo, on the other hand, is exploring something more simple in the form of a cable that connects external video cards to the NVMe M.2 slot inside the laptop.


https://www.notebookcheck.net/Lenovo-demonstrates-NVMe-M-2-alternative-to-Thunderbolt-for-high-end-external-desktop-GPUs-on-AMD-based-notebooks.517045.0.html

[Rog]

Actually it's faster than Thunderbolt 3

[hjpio]

PCIE 3.0*4 will have slightly slower throughput than TB3 or TB4, but you will not need a separate controller (unless you're on Tiger Lake). However, things are getting more interesting when you factor in the fact that AMD is on PCIE 4.0 since 2020, so PCIE 4.0*4 will give you the same througput than PCIE 3.0*8, which is what ASUS is using in their Flow 13 laptop. Up until RTX 3080/3090 PCIE 3.0*8 was all you really needed to fully utilize a GPU. Even with 3080/3090 performance drop should not exceed low single digit %. I would definitely be tempted to buy an AMD laptop with direct connection to spare PCIE 4.0*4 slot and a compatible external desktop GPU enclosure. Way to go!

[xpclient]

I wish it could do 10 GbE networking too like Thunderbolt. Would be great to connect to another AMD laptop to transfer files fast.

[Erik]

However, things are getting more interesting when you factor in the fact that AMD is on PCIE 4.0 since 2020, so PCIE 4.0*4 will give you the same througput than PCIE 3.0*8, which is what ASUS is using in their Flow 13 laptop.

AMD is on PCIE 4 only on desktop and only on CPUs without integrated graphics, both the laptop APUs and the (OEM-only) desktop APUs are limited to PCIE 3:
www.amd.com/en/products/apu/amd-ryzen-9-5980hx (scroll down to the specifications)
www.notebookcheck.net/The-AMD-Ryzen-7-5800G-leaks-with-PCIe-3-0-support-and-a-Radeon-RX-Vega-8-GPU.515844.0.html

[hfm]

This is obviously not as fast as a Thunderbolt connection, since it uses the 4-lane PCIe 3.0 interface,

False. It's faster than Thunderbolt. Only TB4 using full 32Gb/s can get close, but direct 4x PCIe 3.0 will beat TB every time. Now.. it's ridiculously less convenient than TB, which is a deal breaker IMO. It also won't allow you to use the eGPU on the internal display like TB will.

Also, m.2 eGPU solutions have been around forever, check out https://egpu.io/

[_MT_]

You do realize that NVMe is a storage protocol that works over PCIe? I repeat, a storage protocol. It's used by SSDs.

You know what is the biggest advantage of a connector? That you can easily disconnect it. Without connectors, you've got a cable tethering your laptop to a GPU. And the only way to disconnect it is to take it apart. How stupid is that? That's why Asus, Alienware or who else bothered with a proprietary connector. Little things like this are actually important if you want to sell to consumers.

And claiming that TB is faster than x4 PCIe... that's just ridiculous. You do realize that TB controllers have at most x4 PCIe 3.0 connection? So, it can never be faster. At best, you can get the same throughput with some additional latency even before accounting for any limitations of TB itself. How did you get this job?

[NikoB]

There is no more absurd topic. Only for crazy geeks with a bottomless wallet. And the endless shame of AMD with the failure of integration into mobile SoCs, HDMI 2.1, Display Port 2.0 (here and Intel screwed up for 2 years) and USB4.0 ...

And here you can only laugh...with tears in your eyes, seeing the monstrous prices for 3090 and top motherboards already at $1500! I didn't think I would live to see this. Long hello to the Weimar Republic across the planet! Amen!

[what]

There is no more absurd topic. Only for crazy geeks with a bottomless wallet. And the endless shame of AMD with the failure of integration into mobile SoCs, HDMI 2.1, Display Port 2.0 (here and Intel screwed up for 2 years) and USB4.0 ...

And here you can only laugh...with tears in your eyes, seeing the monstrous prices for 3090 and top motherboards already at $1500! I didn't think I would live to see this. Long hello to the Weimar Republic across the planet! Amen!

what in heavens are you actually talking about