diff --git a/shared/mga_drm.h b/shared/mga_drm.h
index 4934414a..5b8f1564 100644
--- a/shared/mga_drm.h
+++ b/shared/mga_drm.h
@@ -73,7 +73,8 @@
 
 #define MGA_CARD_TYPE_G200	1
 #define MGA_CARD_TYPE_G400	2
-#define MGA_CARD_TYPE_G550	3
+#define MGA_CARD_TYPE_G450	3       /* not currently used */
+#define MGA_CARD_TYPE_G550	4
 
 #define MGA_FRONT		0x1
 #define MGA_BACK		0x2