Which expansion port should I use to add 2x 144hz external monitor?
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The rear USB-C port on the RX 7700S Expansion Bag Module supports DisplayPort Alt Mode that can probably drive 4K 144 Hz. (The GPU itself is probably not fast enough to drive 4K 144 Hz in modern games, as it’s around as fast as an RTX 4060.)
HDMI, DisplayPort, and USB-C expansion cards on the rear two ports and the left middle port of the main laptop body will support 4K 144 Hz display output from the integrated Radeon 780M graphics. (HDMI may be limited to 4K 120 Hz. AMD’s spec sheet for the 7840HS/7940HS did not specify HDMI bandwidth besides “HDMI 2.1”.)
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I’m looking to support up to four external display with the internal monitor turned off. Is this possible using the Framework Laptop 16 (AMD Ryzen 7040 series)? 1080p resolution for all external monitors are good enough for myself doing office work.
This is a good ask. I’m looking to connect 3 1440p 165hz displays to mine. Will it support this?
7840HS/7940HS supports four displays, including the internal one. AMD did not specify the maximum resolution for each when three are involved, but they did specify these as the maximum DisplayPort output.
- 7680x4320 @ 60Hz
- 3840x2160 @ 240Hz
- 3440x1440 @ 360Hz
- 2560x1440 @ 480Hz
- 1920x1080 @ 600Hz
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The frame rate at which a game is rendered has nothing to do with the refresh rate of the display. The GPU will output 4k144hz just as well in game as on the desktop
The latest HDMI card (3rd gen) only supports 4k60hz (HDMI 2.0b), but supports higher refresh rates at lower resolution
My Steam Deck, which also uses DP alt over usb-c also caps 4k@60, whether it be type-c to dp or hdmi. I wouldn’t be surprised if the FW 16 had the same limitations.
Granted, the dGPU expansion has it’s own video output options that don’t go through usb-c and should be capable of 4k higher than 60hz.
The display output port on the RX 7700S Expansion Bay Module is USB-C.
Welp. RIP
As there is no native HDMI output, that does not matter at all. That only depends on whatever DP-to-HDMI adapter you use.
It’s primarily there as the most compact form of a DisplayPort output. The USB-C format doesn’t hobble the capabilities.
Most likely the iGPU in the Steam Deck that limiting the resolution support, there’s no way it can push enough pixels to game in 4K @ 120Hz.
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This makes sense. It’s just a shame because even at lower framerates, higher refresh can be beneficial to reduce ghosting and frame-time/refresh deltas on certain display technologies like VA.
We’ll see what the FW supports when it comes out, I’m glad it’s not a limitation of the standard 
So it’s not working as a DP alt mode, but a direct DP output?
It’s DP Alt mode. The port does USB as well, but only USB 2.0.
Has anyone tested the back port much? Best I can get is two monitors through an HDMI adapter with one at 1440p@120hz and the other 1440p@60hz. Any idea if there are better ways out there to get higher refresh or even possibly 3 1440p displays out the back?
The 7700S supports UHBR 13.5 and Displayport 2.1, which is good enough for 4K@240Hz. The problem is that you are more than likely using a DP 1.2 MST Hub or DP 1.4 without DSC, and DP 1.4 can only use HBR3 and makes only half the bandwidth available that the port can support. I’m not aware of any DP 2.0/2.1 MST Hubs on the market, but that’s what you’d need to do 1440P@120Hz x 3 without compression. Alternatively, you might be able to get it to work with DSC if you’re feeling adventurous. You could get one of StarTech’s DP 1.4 to HDMI or Displayport 1.4 MST hubs:
HDMI: 3-Port USB-C to HDMI MST Hub, 4K 60Hz - USB-C Display Adapters | Display & Video Adapters | StarTech.com
DisplayPort: USB-C to Triple DP MST Hub 4K60Hz, DP1.4 - USB-C Display Adapters | Display & Video Adapters | StarTech.com
That MST hub does support DSC, so theoretically you could squeeze 3 in with the dynamic compression.
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Thanks for the detailed explanation on this. I am currently using this one which gets me the two monitors. I will try out that StarTech one to see if I can get all three working.
Monoprice USB-C to Dual 4K HDMI Adapter
Yeah I can’t personally tell from Monoprice’s docs if that dongle supports DSC. I can’t find anything saying it does. DP 1.4 has ~26Gbps of bandwith without compression, and ~49Gbps effective bandwidth with DSC. It takes ~11.6Gbps to stream an uncompressed 1440P@120Hz signal. That’s why there isn’t enough bandwidth without DSC, but hopefully there will be if you get a MST Hub that acts as a DSC sink device, like the StarTech ones above.
I got this one and tested it out a bit. I have to connect it to the laptop without any monitors attached for it to even show up. And then I can connect the three monitors one at a time and they work great. I get 3x1440p@144Hz. It works from the rear usb port or from a side one that supports displays.
Unfortunately, having to disconnect all the monitors from the device and reconnect them in order for it to work every time I want to connect it kind of defeats the purpose of even having one monitor connection. I might as well just buy three HDMI input modules. For the $70 this device costs, it’s unacceptable and going back.
Sure, it’s unfortunate, but that is also obviously not the way the device is supposed to work. Unfortunately, once you get into Active conversion, and MST Hubs, compatibility is not perfect. Those that are used to non-cheap Thunderbolt and USB-C docks from first parties like Dell / HP, etc. will see that there are frequently firmware upgrades for those docks, and those firmware upgrade almost always include updates to the MST Hub to deal with eccentricities connecting certain monitors / TVs / certain laptops or devices. Depending on your appetite you can reach out to both StarTech and Framework, and it might get the ball rolling on a solution either in AMD’s Graphics Drivers, or StarTech’s firmware applied to the device. StarTech may even have a firmware release they could ask you to apply to the device to see if it would stabilize it.
Alternatively, you can also try a full USB-C Dock, however inside a USB-C Hub with multiple video outputs is, no surprise, an MST Hub
That said, by far the simplest option if you can dedicate 3 of your card slots to video outputs, is to simply use the Active HDMI Output modules. Just keep in mind Displayport to HDMI Active converters can have their own display recognition issues too (there’s been a couple threads about that already on here). I’d try it on one before buying more modules if you haven’t already.