With FW platforms already shipping (FW13 AMD, plus FW16 coming soon) that support HDMI 2.1 and DisplayPort 2., how soon should we expect FW to release new expansion cards that support these new standards?
FW seems to have worked quickly to release revisions to the existing HDMI and DP cards but that was motivated by something completely different.
The DisplayPort Expansion Card is mostly a passive passthrough of the DisplayPort signals from the processor, so it supports whatever DisplayPort version the processor supports.
At first Framework advertised the DisplayPort Expansion Card as supporting DisplayPort 1.4 (since at the time that was what was supported by the processors Framework were using), however it has since been updated to say “The DisplayPort Expansion Card passes through DP Alt Mode directly from the Mainboard, enabling support for the maximum DisplayPort version and monitor resolution supported by the processor.”
So the DisplayPort Expansion Card already automatically supports the latest DisplayPort version supported by the CPU.
The CPU doesn’t support outputting HDMI over USB-C, so the HDMI Expansion Card is basically a DisplayPort Expansion Card with a chip that translates DisplayPort into HDMI. So a new HDMI Expansion Card will be needed to get newer HDMI versions.
Thanks, that would be a great outcome and I would love for them to clarify that in the fine print on the product page.
I noticed that change too but never occurred to me that the pass-thru nature could support such an increase in bandwidth!
Yep, with a little bit of circuitry to tell the laptop to supply DP signals to the USB-C port.
TBF, the expansion ports are limited to 40Gbps and full bandwidth HDMI 2.1 is 48Gbps, so some kind of DSC would need to be supported I think. I have absolutely no idea if the iGPU has that feature but I also don’t see the need since the iGPU is so weak. Anything that the iGPU can do can be done with the reduced bandwidth currently possible. Unless you have a different use case?
Isn’t that only when they’re used in Thunderbolt 3 mode?
@jschievink The ports are TB4. The expansion cards just convert that signal into whatever it is they are designed to convert it to. The inherent limitation will always be 40Gbps, no matter what the expansion card supports.
USB-C alternate modes don’t work like that, they reconfigure the lanes of the connector to carry an alternate signal directly, without encapsulating it in thunderbolt.
A TB4 connector is rated for 80 Gbps (plus a separate USB 2.0 connection, but I’m ignoring that because it has its own dedicated bandwidth).
The Thunderbolt 4 protocol splits that bandwidth into 40 Gbps in each direction, however DisplayPort alt mode (where the connector is carrying a DisplayPort signal directly instead of Thunderbolt) doesn’t have that restriction because DisplayPort has no need for symmetric bandwidth. (Thunderbolt 5 also supports asymmetric bandwidth)
I strongly suspect that one of the reasons why the DP 2.0/2.1 UHBR20 is exactly 80 Gbps is so it can take full advantage of the 80 Gbps available through a cable rated for Thunderbolt 4.