diff --git a/flake.nix b/flake.nix
index 6c295db3..8382a8e0 100644
--- a/flake.nix
+++ b/flake.nix
@@ -310,7 +310,6 @@
 
         dacbert = nixosSystem' {
           modules = [
-            "${inputs.nixpkgs}/nixos/modules/installer/sd-card/sd-image-aarch64.nix"
             nixos-hardware.nixosModules.raspberry-pi-4
             self.nixosModules.rpi-netboot
             ./hosts/dacbert
diff --git a/hosts/containers/nix-build/rpi-netboot.nix b/hosts/containers/nix-build/rpi-netboot.nix
index 2a2daab5..5dca37bd 100644
--- a/hosts/containers/nix-build/rpi-netboot.nix
+++ b/hosts/containers/nix-build/rpi-netboot.nix
@@ -2,12 +2,13 @@
 let
   tftpRoot = pkgs.runCommand "tftproot" {} ''
     mkdir $out
-    cp -sr ${tftproots.rpi-netboot-tftproot} $out/
+    cp -sr ${tftproots.rpi-netboot-tftproot}/* $out/
     ${lib.concatMapStrings (host: ''
-      ln -s ${tftproots."${host}-tftproot"} $out/${hostRegistry.${host}.serial}
+      ln -s ${tftproots."${host}-tftproot"} $out/${hostRegistry.hosts.${host}.serial}
     '') (
       builtins.attrNames (
-        lib.filterAttrs (_: { serial ? null, ... }: serial != null) hostRegistry
+        lib.filterAttrs (_: { serial ? null, ... }: serial != null)
+          hostRegistry.hosts
       )
     )}
   '';
diff --git a/hosts/dacbert/default.nix b/hosts/dacbert/default.nix
index 888face5..080e4604 100644
--- a/hosts/dacbert/default.nix
+++ b/hosts/dacbert/default.nix
@@ -1,29 +1,11 @@
-{ config, lib, pkgs, modulesPath, ... }:
+{ hostRegistry, config, lib, pkgs, modulesPath, ... }:
 
 {
-  boot.initrd.kernelModules = [ ];
-  boot.initrd.includeDefaultModules = false;
-  boot.initrd.availableKernelModules = lib.mkForce [ "usbhid" ];
-  boot.kernelModules = [ ];
-  boot.extraModulePackages = [ ];
-
-  fileSystems."/" = {
-    device = "/dev/disk/by-label/NIXOS_SD";
-    fsType = "ext4";
-  };
-
-  fileSystems."/boot/firmware" = {
-    device = "/dev/disk/by-label/FIRMWARE";
-    fsType = "vfat";
-  };
-
-  swapDevices = [ ];
-
   hardware.enableRedistributableFirmware = true;
-  hardware.deviceTree = {
-    enable = true;
-    kernelPackage = config.boot.kernelPackages.kernel;
-  };
+  # hardware.deviceTree = {
+  #   enable = true;
+  #   kernelPackage = config.boot.kernelPackages.kernel;
+  # };
   powerManagement.cpuFreqGovernor = lib.mkDefault "performance";
 
   nixpkgs.config.packageOverrides = pkgs: {
@@ -39,15 +21,13 @@
         enable = true;
         version = 4;
         firmwareConfig = ''
-          gpu_mem=192
+          gpu_mem=256
           dtparam=audio=on
         '';
       };
     };
-    kernelPackages = pkgs.linuxPackages_latest;
+    # kernelPackages = lib.mkForce pkgs.linuxPackages_latest;
 
-    # No ZFS on latest kernel:
-    supportedFilesystems = lib.mkForce [ "vfat" "ext4" ];
     kernelParams = lib.mkForce [
       "snd_bcm2835.enable_headphones=1"
       # don't let sd-image-aarch64.nix setup serial console as it breaks bluetooth.
@@ -56,13 +36,8 @@
 
     tmpOnTmpfs = true;
   };
-  sdImage = {
-    compressImage = false;
-    imageBaseName = config.networking.hostName;
-    firmwareSize = 512;
-  };
   hardware.raspberry-pi."4" = {
-    # fkms-3d.enable = true;
+    fkms-3d.enable = true;
   };
 
   c3d2 = {
@@ -72,7 +47,6 @@
     hq.statistics.enable = true;
     audioServer.enable = true;
     k-ot.enable = true;
-    autoUpdate = true;
   };
 
   nix = {
diff --git a/modules/rpi-netboot.nix b/modules/rpi-netboot.nix
index e03d6921..8d2dc7b7 100644
--- a/modules/rpi-netboot.nix
+++ b/modules/rpi-netboot.nix
@@ -4,6 +4,9 @@
     loader.raspberryPi = {
       enable = true;
       version = 4;
+      firmwareConfig = lib.mkDefault ''
+        gpu_mem=256
+      '';
     };
     kernelPackages = pkgs.linuxPackages_rpi4;
     kernelParams = [
@@ -57,7 +60,9 @@
     # r/o /nix/store
     services.nix-daemon.enable = false;
     sockets.nix-daemon.enable = false;
+    services.nix-gc.enable = false;
   };
+  nix.gc.automatic = lib.mkForce false;
   services.journald.extraConfig = ''
     Storage=volatile
   '';
@@ -71,9 +76,9 @@
     cat << EOF > $out/config.txt
     kernel=kernel8.img
     initramfs initrd.img followkernel
-    gpu_mem=256
     arm_64bit=1
+    ${toString config.boot.loader.raspberryPi.firmwareConfig}
     EOF
-    echo "dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 verbose init=${config.system.build.toplevel}/init" > $out/cmdline.txt
+    echo "dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 verbose init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams}" > $out/cmdline.txt
   '';
 }