--- 915resolution/915resolution.c
+++ 915resolution/915resolution.c
@@ -66,12 +66,12 @@
 
 typedef enum {
     CT_UNKWN, CT_830, CT_845G, CT_855GM, CT_865G, CT_915G, CT_915GM, CT_945G, CT_945GM, CT_945GME,
-    CT_946GZ, CT_G965, CT_Q965
+    CT_946GZ, CT_G965, CT_Q965, CT_500GMA
 } chipset_type;
 
 char * chipset_type_names[] = {
     "UNKNOWN", "830",  "845G", "855GM", "865G", "915G", "915GM", "945G", "945GM", "945GME",
-    "946GZ",   "G965", "Q965"
+    "946GZ",   "G965", "Q965", "500GMA"
 };
 
 typedef enum {
@@ -226,6 +226,10 @@
         type = CT_Q965;
         break;
 
+    case 0x81008086:
+      type = CT_500GMA;
+      break;
+
     default:
         type = CT_UNKWN;
         break;
@@ -446,6 +450,7 @@
     case CT_946GZ:
     case CT_G965:
     case CT_Q965:
+    case CT_500GMA:
         grub_outl(0x80000090, 0xcf8);
         map->b1 = grub_inb(0xcfd);
         map->b2 = grub_inb(0xcfe);
@@ -485,6 +490,7 @@
     case CT_946GZ:
     case CT_G965:
     case CT_Q965:
+    case CT_500GMA:
         grub_outl(0x80000090, 0xcf8);
         grub_outb(map->b1, 0xcfd);
         grub_outb(map->b2, 0xcfe);
@@ -756,6 +762,9 @@
         else if (!grub_strcmp(argv[index], "Q965")) {
             *forced_chipset = CT_Q965;
         }
+	else if (!grub_strcmp(argv[index], "500GMA")) {
+	    *forced_chipset = CT_500GMA;
+	}
         else {
             *forced_chipset = CT_UNKWN;
         }