diff --git a/install.sh b/install.sh
index 106dfe8..5e7769f 100644
--- a/install.sh
+++ b/install.sh
@@ -87,24 +87,42 @@ fi
 DETECTED_CUDA="$(nvidia-smi | grep 'CUDA Version' | sed 's/.*CUDA Version: *\([0-9.]*\).*/\1/')"
 log "Detected CUDA capability: ${DETECTED_CUDA}"
 
+# Extract major.minor (e.g., 12.4)
+DETECTED_MM="$(echo "$DETECTED_CUDA" | cut -d. -f1,2)"
+
 choose_cuda() {
-  # Pick highest supported version <= detected CUDA capability
-  for v in $(printf '%s\n' "${SUPPORTED_CUDA[@]}" | sort -rV); do
-    if [ "$(printf '%s\n%s\n' "$v" "$DETECTED_CUDA" | sort -V | head -n1)" = "$v" ]; then
-      echo "$v"
-      return 0
+  local best=""
+  local best_mm=""
+
+  for v in "${SUPPORTED_CUDA[@]}"; do
+    v_mm="$(echo "$v" | cut -d. -f1,2)"
+
+    # Only consider versions with same major.minor
+    if [ "$v_mm" = "$DETECTED_MM" ]; then
+      # Pick highest patch of that minor
+      if [ -z "$best" ] || [ "$(printf '%s\n%s\n' "$best" "$v" | sort -V | tail -n1)" = "$v" ]; then
+        best="$v"
+      fi
     fi
   done
+
+  if [ -n "$best" ]; then
+    echo "$best"
+    return 0
+  fi
+
   return 1
 }
 
 if CUDA_VERSION="$(choose_cuda)"; then
   log "Selected CUDA image version: ${CUDA_VERSION}"
 else
-  warn "Could not auto-match CUDA version, defaulting to highest supported"
-  CUDA_VERSION="$(printf '%s\n' "${SUPPORTED_CUDA[@]}" | sort -V | tail -n1)"
+  err "No compatible CUDA image found for driver capability ${DETECTED_MM}.x"
+  err "Supported versions: ${SUPPORTED_CUDA[*]}"
+  exit 1
 fi
 
+
 IMAGE="${IMAGE_BASE}/${CUDA_VERSION}/tentacle:${IMAGE_TAG}"
 
 # -----------------------------