diff --git a/iso/builder/build-debug.sh b/iso/builder/build-debug.sh
index 69b43d4..ae4be33 100644
--- a/iso/builder/build-debug.sh
+++ b/iso/builder/build-debug.sh
@@ -104,7 +104,7 @@ echo "=== building NVIDIA ${NVIDIA_DRIVER_VERSION} modules ==="
 sh "${BUILDER_DIR}/build-nvidia-module.sh" "${NVIDIA_DRIVER_VERSION}" "${DIST_DIR}"
 
 # Determine kernel version (same as what goes into the ISO — both use linux-lts from same Alpine)
-KVER=$(ls /usr/src/ 2>/dev/null | grep '^linux-headers-' | sed 's/linux-headers-//' | head -1)
+KVER=$(ls /usr/src/ 2>/dev/null | grep '^linux-headers-' | sed 's/linux-headers-//' | sort -V | tail -1)
 NVIDIA_CACHE="${DIST_DIR}/nvidia-${NVIDIA_DRIVER_VERSION}-${KVER}"
 
 # Inject .ko files into overlay at /lib/modules/<kver>/extra/nvidia/
diff --git a/iso/builder/build-nvidia-module.sh b/iso/builder/build-nvidia-module.sh
index b9b3dc3..dd6994a 100644
--- a/iso/builder/build-nvidia-module.sh
+++ b/iso/builder/build-nvidia-module.sh
@@ -20,12 +20,20 @@ DIST_DIR="$2"
 [ -n "$NVIDIA_VERSION" ] || { echo "usage: $0 <nvidia-version> <dist-dir>"; exit 1; }
 [ -n "$DIST_DIR" ]       || { echo "usage: $0 <nvidia-version> <dist-dir>"; exit 1; }
 
-# Detect kernel version from installed headers
-KVER=$(ls /usr/src/ 2>/dev/null | grep '^linux-headers-' | sed 's/linux-headers-//' | head -1)
+# Detect kernel version from installed headers (pick highest version if multiple).
+detect_kver() {
+    ls /usr/src/ 2>/dev/null \
+        | grep '^linux-headers-' \
+        | sed 's/linux-headers-//' \
+        | sort -V \
+        | tail -1
+}
+
+KVER="$(detect_kver)"
 if [ -z "$KVER" ]; then
     echo "=== installing linux-lts-dev ==="
     apk add --quiet linux-lts-dev
-    KVER=$(ls /usr/src/ | grep '^linux-headers-' | sed 's/linux-headers-//' | head -1)
+    KVER="$(detect_kver)"
 fi
 KDIR="/usr/src/linux-headers-${KVER}"
 echo "=== NVIDIA ${NVIDIA_VERSION} (proprietary) for kernel ${KVER} ==="
diff --git a/iso/builder/build.sh b/iso/builder/build.sh
index 69d1e0d..265a6a5 100755
--- a/iso/builder/build.sh
+++ b/iso/builder/build.sh
@@ -43,7 +43,7 @@ done
 # Build and inject NVIDIA proprietary modules + userspace tools.
 echo "=== building NVIDIA modules ==="
 sh "${BUILDER_DIR}/build-nvidia-module.sh" "${NVIDIA_DRIVER_VERSION}" "${DIST_DIR}"
-KVER="$(ls /usr/src/ 2>/dev/null | grep '^linux-headers-' | sed 's/linux-headers-//' | head -1)"
+KVER="$(ls /usr/src/ 2>/dev/null | grep '^linux-headers-' | sed 's/linux-headers-//' | sort -V | tail -1)"
 NVIDIA_CACHE="${DIST_DIR}/nvidia-${NVIDIA_DRIVER_VERSION}-${KVER}"
 
 mkdir -p "${OVERLAY_DIR}/lib/modules/${KVER}/extra/nvidia"
diff --git a/iso/overlay-debug/etc/init.d/bee-nvidia b/iso/overlay-debug/etc/init.d/bee-nvidia
index f4f6fe3..0cc4914 100755
--- a/iso/overlay-debug/etc/init.d/bee-nvidia
+++ b/iso/overlay-debug/etc/init.d/bee-nvidia
@@ -9,6 +9,15 @@ depend() {
 
 start() {
     ebegin "Loading NVIDIA modules"
+    kver="$(uname -r)"
+    einfo "kernel: ${kver}"
+    if [ -d "/lib/modules/${kver}/extra/nvidia" ]; then
+        einfo "module dir: /lib/modules/${kver}/extra/nvidia"
+        ls "/lib/modules/${kver}/extra/nvidia"/*.ko 2>/dev/null | sed 's/^/  /' || true
+    else
+        ewarn "module dir missing: /lib/modules/${kver}/extra/nvidia"
+    fi
+
     # Run depmod so kernel can locate our modules in /lib/modules/.../extra/
     depmod -a 2>/dev/null || true
 
@@ -17,6 +26,7 @@ start() {
             einfo "loaded: $mod"
         else
             ewarn "failed to load: $mod"
+            dmesg | tail -n 5 | sed 's/^/  dmesg: /' || true
         fi
     done
     eend 0
diff --git a/iso/overlay/etc/init.d/bee-nvidia b/iso/overlay/etc/init.d/bee-nvidia
index c250f02..62b9e62 100755
--- a/iso/overlay/etc/init.d/bee-nvidia
+++ b/iso/overlay/etc/init.d/bee-nvidia
@@ -9,6 +9,15 @@ depend() {
 
 start() {
     ebegin "Loading NVIDIA modules"
+    kver="$(uname -r)"
+    einfo "kernel: ${kver}"
+    if [ -d "/lib/modules/${kver}/extra/nvidia" ]; then
+        einfo "module dir: /lib/modules/${kver}/extra/nvidia"
+        ls "/lib/modules/${kver}/extra/nvidia"/*.ko 2>/dev/null | sed 's/^/  /' || true
+    else
+        ewarn "module dir missing: /lib/modules/${kver}/extra/nvidia"
+    fi
+
     depmod -a 2>/dev/null || true
 
     for mod in nvidia nvidia-modeset nvidia-uvm; do
@@ -16,6 +25,7 @@ start() {
             einfo "loaded: $mod"
         else
             ewarn "failed to load: $mod"
+            dmesg | tail -n 5 | sed 's/^/  dmesg: /' || true
         fi
     done