diff --git a/src/mess/drivers/at.c b/src/mess/drivers/at.c
index be21b73262a..400719ce229 100644
--- a/src/mess/drivers/at.c
+++ b/src/mess/drivers/at.c
@@ -858,14 +858,17 @@ IBM Personal System/2 Model 65 SX (8565-061 and 8565-121)
 */
 ROM_START( i8550021 )
     ROM_REGION(0x1000000,"maincpu", 0)
-	ROM_LOAD16_BYTE( "90x7423.bin", 0xe0000, 0x8000, CRC(2c1633e0) SHA1(1af7faa526585a7cfb69e71d90a75e1f1c541586))
+	ROM_LOAD16_BYTE( "90x7423.zm14", 0xe0000, 0x8000, CRC(2c1633e0) SHA1(1af7faa526585a7cfb69e71d90a75e1f1c541586))
 	ROM_RELOAD(0xfe0000, 0x8000)
-	ROM_LOAD16_BYTE( "90x7426.bin", 0xe0001, 0x8000, CRC(e7c762ce) SHA1(228f67dc915d84519da7fc1a59b7f9254278f3a0))
+	ROM_LOAD16_BYTE( "90x7426.zm16", 0xe0001, 0x8000, CRC(e7c762ce) SHA1(228f67dc915d84519da7fc1a59b7f9254278f3a0))
 	ROM_RELOAD(0xfe0001, 0x8000)
-	ROM_LOAD16_BYTE( "90x7420.bin", 0xf0001, 0x8000, CRC(19a57cc1) SHA1(5b31ba66cd3690e651a450619a32b7210769945d))
+	ROM_LOAD16_BYTE( "90x7420.zm13", 0xf0001, 0x8000, CRC(19a57cc1) SHA1(5b31ba66cd3690e651a450619a32b7210769945d))
 	ROM_RELOAD(0xff0001, 0x8000)
-	ROM_LOAD16_BYTE( "90x7429.bin", 0xf0000, 0x8000, CRC(6f0120f6) SHA1(e112c291ac3d9f6507c93ac49ad26f9fd2245fd2))
+	ROM_LOAD16_BYTE( "90x7429.zm18", 0xf0000, 0x8000, CRC(6f0120f6) SHA1(e112c291ac3d9f6507c93ac49ad26f9fd2245fd2))
 	ROM_RELOAD(0xff0000, 0x8000)
+
+	ROM_REGION( 0x800, "keyboard", 0 )
+	ROM_LOAD( "72x8455.zm82", 0x000, 0x800, CRC(7da223d3) SHA1(54c52ff6c6a2310f79b2c7e6d1259be9de868f0e) )
 ROM_END
 
 /*