Performance observation (with fix / workaround): FL13 Intel 11th Gen + AMD AI Pro R9700 + Razer Core X + LM Studio

Framework Laptop 13
,
1

Background:
For whatever reason, the R9700 in the Core X would perform very poorly in LM Studio.

Software:
Windows 11 25H2
AMD Adrenaline 26.3.1
LM Studio 0.47 + Vulkan runtime 2.8.0 + Qwen 3.5 35B A3B Q4_K_M

Hardware:
Framework Laptop 13 11th Gen
Razer Core X (first gen)
AMD R9700
1 metre TB cable (to Core X, from bottom / away-from-hinge left)
100w USB-PD (connected to top / close-to-hinge left)

Scenario replication:

  1. Windows 11 without AMD driver yet.
  2. LM Studio and model already installed (and able to run with tg rate at around 12-15tk/s based on the CPU with the Vulkan runtime)
  3. Plug in the Core X. R9700 is seen as Basic Graphics or something, as expected without the GPU driver.
  4. Install Adrenaline 26.3.1 → Custom → Driver only.
  5. Do not reboot yet.
  6. Start LM Studio, Runtime is Vulkan 2.8.0 with R9700 selected, run a chat session with Qwen 3.5 35B. Getting around 95-98tk/s (acceptable / fine).
  7. Reboot
  8. Start LM Studio again, run a new chat or continue the chat (doesn’t matter) with Qwen 3.5 35B, now only getting only about 15tk/s. Checked the GPU memory utilization (21-22GB), Checked the GPU power (130W).

The fix / workaround:

  1. Set GGML_VK_DISABLE_HOST_VISIBLE_VIDMEM=1 in environment variable…when (and only when) the R9700 is connected.
  2. Dynamically set / unset the above env variable in PowerShell prior to launching LM Studio. Create a shortcut to the script.

Result:
Now getting 95-98tk/s again when the R9700 is connected. When it’s not connected, the CPU would be used instead and getting 13-15tk/s again.

Note:
If GGML_VK_DISABLE_HOST_VISIBLE_VIDMEM=1 is set when using the CPU for inference, the tg speed would drop to around 8tk/s. That’s why it needs to be unset.

Not sure if it’s going to help anyone, or if there’s a better fix (I’m new to all of this AI stuff). Let me know if there’s a better solution (excluding “Use Linux”…I have that on another system).

(Yes, aware of the fact that I’m not getting the best performance over TB…that’s for another build when I can eventually afford some desktop RAM)

Update (2026-04-05): Removed wording of “issue”…More like a “I didn’t know jack” thing.