Like many of you, I’m very excited (and surprised) by the announcement of the 5070 graphics expansion module. I’m sure it was great for many, bur the 7700s just never felt like it could quite get the job done for my use case, and one of the contributing factors was that it didn’t support 4k/120hz natively (I forget what the specific display protocol is called, but FW support confirmed it for me). I was able to get a lower bit depth version of it to work after trying a few different adapters, but it was a bummer that it didn’t support it natively since I use a couple of different workstations with 4k/120 panels every day.
I wanted to check and see if anyone might have a sense of whether or not the 5070 will suffer from the same fate or support it natively at full color fidelity? I know Nirav mentioned some of the exciting improvements in functionality to that rear port, but did not mention anything about this improved display protocol.
The RX 7700S supports 4k 120Hz with an appropriately rated cable. I’m running it that way right now with an LG Ultragear OLED. The trick is you must use the USB C jack on the dGPU. It can work through the MUX and one of the side USB C jacks, but it’s a lot more unreliable.
For the RTX 5070, no reason why it will be any different.
If the side USB-C supports it you should also be able to use the DP expansion card. It is basically a passthrough of the DP signal present in the USB-C port.
In my experience, not all programs like to run high refresh, rendered on the dGPU, through the MUX. The best example I can think of is Autodesk Fusion, which will simply refuse to render on the dGPU at 4k 120Hz when connected through the MUX. Even more fun was the discovery that nothing but the original graphics driver for the 16 would allow Autodesk Fusion to render on the dGPU, through the MUX, and through my CalDigit TS4 docking station. I did not try the DP expansion card, but both the 3rd gen HDMI and my current USB-C to HDMI 2.1 cable did not want to play along.
So, yes the side USB-C ports support 4k 120Hz, but you may encounter fun issues with almost no explanation. I also strongly recommend bypassing any docking station for 4k 120Hz, after 6 months of troubleshooting my CalDigit TS4.
I appreciate the input, folks. I should have specified that my panels are OLED TVs, so HDMI is the only game in town. I think that’s the biggest bottleneck since the HDMI adapter is (currently) only 2.0b. I was able to find an HDMI to USB C adapter (which wasn’t cheap) that allows me to do 4k/120 HDR at 10-bit, but it still looked a little iffy. Other laptops I have with HDMI 2.1 are smooth sailing at 4k/120/12-bit HDR.
Here’s a previous thread where Kyle gave an incredibly detailed explanation of the shortcomings of the 7700s/port. I’m hoping the 5070 won’t have the same limitations.
I have the same issue on my Linux desktop with AMD. The HDMI Forum wants to keep everything proprietary, so HDMI 2.1 and open source drivers don’t mix. I also went the route of adapters and couldn’t find anything that worked 100%, even tho it should be possible.
What kind of cable? I’d love to use the port in the back for my monitor. Currently running 1440p 240 Hz which requires HDMI 2.1 which I have to use a usb4 to HDMI 2.1 adapter in one if the side ports
For anyone else interested, if you care about VRR/Freesync, this adapter might not be able to do it. That was always my hangup when looking at adapters.
