AMD 7040U can't seem to drive two monitors at greater than 60Hz

Framework Laptop 13
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Hey all,

Happy to join the community. I wanted to post an issue that I just noticed with my newly purchased Framework 13 with an AMD 7040U running an up-to-date Fedora 39.

I have a ThinkPad Universal Thunderbolt 4 Dock for my work laptop. I have recently been testing it with my Framework, and besides the power button not working, it works great. I have two Dell monitors with DIsplayPort 1.4 that support up to 165Hz, but have settings for 90Hz, 120Hz, and 144Hz in addition to 60Hz. By default, they are running at 60Hz.

Today, I finally got around to adjusting the refresh rates on my monitors through GNOME Settings (formerly GNOME Control Center). I changed one of my monitors to 165Hz, and then proceeded to change the other. But when I changed the 2nd one, the displays went to sleep. I could wake them with the mouse afterward. I went to check if the setting had applied, but it got set back to 60Hz for the 2nd monitor, the first still running at 165Hz. I then tried to set both monitors to 90Hz, but I had the same issues.

I have a ThinkPad X1 Carbon as my work laptop, and it drives these monitors through the dock at 165Hz just fine. I want to determine the limiting factor here. Is it the hardware or the firmware? I know it isn’t the dock, the monitors, or my KVM switch (Level1Techs) because everything works fine with my work laptop, but that is also a ThinkPad laptop talking to a ThinkPad dock.

Has anyone else experienced similar issues? Running my monitors at 60Hz is fine, but it is annoying to not be able to use my hardware to its full potential.

1 Like
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My dad got the ThinkPad Universal USB-C Dock for his AMD Framework, and is having the same issues, which definitely confirms a hardware limitation or firmware issue with the laptop itself.

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Is this the dock you are taking about? https://www.lenovo.com/us/en/p/accessories-and-software/docking/docking_usb-docks-(universal-cable-docks)/40ay0090us#tech_specs

If you read the specs on it, it can only do 60hz at best.

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For my father’s dock, this would be the one. Though he uses 2 2K monitors, same as me.

One display: 7680 x 4320 @ 30hz by HDMI port, Two displays: 2 x 3840 x 2160 @ 60Hz, Three displays: 2 x 3840 x 2160 @ 60Hz + 1 x 3840 x 2160 @ 30Hz

Seems like the dock should be able to drive 2 2K monitors at > 60Hz.

To be more specific in my situation, my dock is this, and like I said, I know for a fact that it can drive 2 2K monitors at 165Hz because I do it for work.

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A brief search of the forums suggests driving via usb4 is also a limitation.

I am quite happy at 60hz, but I don’t use my laptop for casual gaming either…Perhaps the HDMI modules would give you that sweet 144hz?

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Good find, but that says 2 8K@60Hz. I just want to drive 2 2K at anything greater than 60Hz. Doing silly mental math, 2 8K@60Hz is equal to 2 2K@240Hz. Am I crazy?

I am quite happy at 60hz, but I don’t use my laptop for casual gaming either…Perhaps the HDMI modules would give you that sweet 144hz?

It would be really annoying if I couldn’t use a docking station to just have one input cable into my Framework laptop.

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Your bandwidth and speed is essentially as fast as the slowest, narrowest link in your chain. If you think it’s the laptop, eliminate all the things between the monitors and the laptop. That’s why I suggested it. Though as I wrote this comment up, I realized you probably want DisplayPort (DP), not HDMI? And as I read those specs, I think you are kind of limited anyway.

Here’s Framework | DisplayPort (1st Gen) Expansion Card. Looking at the spec, you aren’t getting anything above 60hz.

Then I realized it was a first gen expansion card…Framework | DisplayPort (2nd Gen) Expansion Card

Well, no clear spec, but “Passes through DP Alt Mode directly from the Mainboard, enabling support for the maximum DisplayPort version and monitor resolution supported by the processor.”

Looking at the HDMI expansion card at Framework | HDMI (3rd Gen) Expansion Card, “Supports HDMI 2.0b for resolutions up to 4k 60Hz, along with audio output. You can use multiple simultaneously to handle additional monitors, up to the number your processor supports.”

So…USB-C…Framework | USB-C Expansion Card
“Supports USB4
Supports 48V/5A charging
Supports DisplayPort Alt Mode up to 8k 60Hz”

Quickly reading all that, I think DisplayPort Alt Mode is our least bottle-necked (at least on paper) option. Let’s look at the CPU capabilities…https://www.amd.com/en/products/apu/amd-ryzen-5-7640u and https://www.amd.com/en/products/apu/amd-ryzen-7-7840u

That tells you they include either 760M or 780M grahpics card respectively…https://www.amd.com/en/graphics/amd-radeon-rx-laptops. Damn…Nothing. The best we can do is look elsewhere for specs, maybe?

Yep! Found https://www.amd.com/en/product/13196 and https://www.amd.com/en/product/13186.
You need to see that kind-of unobvious “see full specifications” at the bottom of the AMD CPU spec sheets…

Now I really think it comes down to if you can pass DisplayPort Alt mode. A new thought: If you want one cable, consider DisplayPort MST (daisy-chaining) if possible?

Back to your docks…Your dad’s supports: Video Ports 2 x DP 1.4, 1 x HDMI 2.1 and yours supports: Video Ports 1* HDMI 2.1 2* DP 1.4
(love how they flop the specs on each, but wind up the same anyway). But they don’t clearly state if they supports MST. Does it need to at that the hub’s point of view? It’s DP 1.4.

Add all the specs up and you get ¯\_(ツ)_/¯

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So what I guess I haven’t made clear is that my Framework is using 4 USB-C expansion cards, ie, no DP expansion cards. I have everything hooked into the Thunderbolt 4 dock mentioned earlier, which has one Thunderbolt 4 cable plugged into one of the USB4 (USB-C) ports on my Framework.

Could the USB-C expansion card be the limiting factor?

Supports DisplayPort Alt Mode up to 8k 60Hz resolution

From the docs of the USB-C expansion card, it doesn’t sound like it.

I agree that dumpster diving for these specs is hard.

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I think it’s that you aren’t able to use DP Alt Mode on the USB4 side. It could be the monitors, or the dock. Well, that the other modes are limiting your refresh rate without it anyway.

Another fun thread: https://www.reddit.com/r/UsbCHardware/comments/qtm3vj/thunderbolt_4_and_dp_alt_mode/

Now we don’t get thunderbolt spec because AMD isn’t Intel. Does that affect how all that works together?

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The monitors and dock work great at 165Hz for my work laptop which is a Lenovo ThinkPad X1 Carbon, so that’s not it.

I understand so little…

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That’s an Intel laptop with Thunderbolt 4 using a Thunderbolt 4 dock. Sadly, not apples to apples spec-wise. USB4 (the best AMD is likely to get as Intel specifies and certifies Thunderbolt) doesn’t likely equate completely to Thunderbolt4.

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In my awful quest to understand where we sit, here’s more information from @Kyle_Reis: Thunderbolt support on AMD Ryzen - #5 by Kyle_Reis.