System Freez while rebuild

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1

Hello
Yesterday I installed my new gpu (7900xt). Ran some stress tests (CPU and GPU at the same time) without any issues. Today i wanted to install open-web-ui. However when the rebuilding process reaches the building phase of rocblas-tensile-gfx10-5.7.1 my whole system freezes.
I can’t change tty, move my mouse, nothing. However I can hear my fans spinning up and after some time down again. Than the ramp up again.
But I can stop the rebuild with ctrl +c but it takes some time until this input is processed (just took 2-3 Minutes after pressing until the rebuild got stopped.
Here is my config for my gpu:

{config,pkgs,lib,inputs,...}:
{
  boot.initrd.kernelModules = [ "amdgpu" ];
  nixpkgs.config.rocmSupport = true;

  hardware.graphics = {
    enable = true;
    enable32Bit = true;
    extraPackages = [ pkgs.rocmPackages.clr.icd ];
  };
  hardware.amdgpu.opencl.enable = true;
  hardware.amdgpu.amdvlk.enable = true;

  services.xserver.videoDrivers = ["amdgpu"];

  environment.systemPackages = with pkgs; [
    lact
    rocmPackages.clr.icd
  ];

  systemd.tmpfiles.rules = [
    "L+    /opt/rocm   -    -    -     -    ${pkgs.rocmPackages.clr}"
  ];

  systemd.services.lact = {
    description = "AMDGPU Control Daemon";
    after = ["multi-user.target"];
    wantedBy = ["multi-user.target"];
    serviceConfig = {
      ExecStart = "${pkgs.lact}/bin/lact daemon";
    };
    enable = true;
  };
}

And here is the relevant part for Web-UI (enabled to false so I can rebuild again):

  services.ollama = {
    enable = true;
    acceleration = "rocm";
    environmentVariables = {
      HSA_OVERRIDE_GFX_VERSION = "11.0.0";
    };
  };

  services.open-webui = {
    enable = false;
  };

System Info:
Hardware

  • MSI Z790-p Wifi
  • Intel Core i5 14600kf
  • Radeon 7900xt
  • be quiet 850 Watt psu

Software

  • NixOS 25.05 (Warbler) x86_64
  • Linux 6.13.0

Thanks in advance for any help.