External AMD GPU attached to laptop with Intel and NVidia GPUs

I have a Dell laptop with Intel and Nvidia GPU and Sonnet 750 eGPU enclosure with AMD card. Monitor is connected via USB-C to laptop.

glxinfo correctly shows AMD GPU as renderer when I run

<span style="color:#323232;"># DRI_PRIME=1 glxinfo | grep "OpenGL renderer"
</span><span style="color:#323232;">OpenGL renderer string: AMD Radeon RX 7900 XTX (gfx1100, LLVM 17.0.6, DRM 3.54, 6.6.9-1-default)
</span>

When I try to run steam or benchmark like Superposition though, they run using Intel card with terrible performance.

DRI_PRIME=1 ./Unigine_Superposition-1.1/bin/launcher

https://lemmy.sdf.org/pictrs/image/1716d204-6ee9-4548-8e80-03af72726fc9.png

You can see in the screenshot that it shows computer RAM (64GB) and not GPU’s VRAM (24GB)

This same setup works perfectly if I put NVidia GPU in the eGPU enclosure.

Any ideas? I tried connecting a DP cable directly from AMD GPU to monitor, but it works like crap with screen barely refreshing.