diff --git a/src/mame/drivers/naomi.c b/src/mame/drivers/naomi.c
index 6ae32ebcef8..662ece081a3 100644
--- a/src/mame/drivers/naomi.c
+++ b/src/mame/drivers/naomi.c
@@ -1567,6 +1567,7 @@ EPR-21576e - NAOMI BOOT ROM 2000 08/25  1.50 (Japan)
 EPR-21576d - NAOMI BOOT ROM 1999 06/04  1.40 (Japan)
 EPR-21576b - NAOMI BOOT ROM 1999 02/15  1.20 (Japan)
 EPR-21576  - NAOMI BOOT ROM 1998 12/18  1.00 (Japan)
+EPR-21577g - NAOMI BOOT ROM 2001 09/10  1.70 (USA)
 EPR-21577e - NAOMI BOOT ROM 2000 08/25  1.50 (USA)
 EPR-21577d - NAOMI BOOT ROM 1999 06/04  1.40 (USA)
 EPR-21578e - NAOMI BOOT ROM 2000 08/25  1.50 (Export)
@@ -1640,12 +1641,14 @@ Scan ROM for the text string "LOADING TEST MODE NOW" back up four (4) bytes for
 	ROM_LOAD16_WORD_SWAP_BIOS( 7, "epr-21578d.bin",  0x000000, 0x200000, CRC(dfd5f42a) SHA1(614a0db4743a5e5a206190d6786ade24325afbfd) ) \
 	ROM_SYSTEM_BIOS( 8, "bios8", "epr-21578b (Export)" ) \
 	ROM_LOAD16_WORD_SWAP_BIOS( 8, "epr-21578b.bin",  0x000000, 0x200000, CRC(6c9aad83) SHA1(555918de76d8dbee2a97d8a95297ef694b3e803f) ) \
-	ROM_SYSTEM_BIOS( 9, "bios9", "epr-21577e (USA)" ) \
-	ROM_LOAD16_WORD_SWAP_BIOS( 9, "epr-21577e.bin",  0x000000, 0x200000, CRC(cf36e97b) SHA1(b085305982e7572e58b03a9d35f17ae319c3bbc6) ) \
-	ROM_SYSTEM_BIOS( 10, "bios10", "epr-21577d (USA)" ) \
-	ROM_LOAD16_WORD_SWAP_BIOS( 10, "epr-21577d.bin",  0x000000, 0x200000, CRC(60ddcbbe) SHA1(58b15096d269d6df617ca1810b66b47deb184958) ) \
-	ROM_SYSTEM_BIOS( 11, "bios11", "Naomi Dev BIOS" ) \
-	ROM_LOAD16_WORD_SWAP_BIOS( 11,  "dcnaodev.bios", 0x000000, 0x080000, CRC(7a50fab9) SHA1(ef79f448e0bf735d1264ad4f051d24178822110f) ) /* This one comes from a dev / beta board. The eprom was a 27C4096 */
+	ROM_SYSTEM_BIOS( 9, "bios9", "epr-21577g (USA)" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 9, "epr-21577g.bin",  0x000000, 0x200000, CRC(25f64af7) SHA1(99f9e6cc0642319bd2da492611220540add573e8) ) \
+	ROM_SYSTEM_BIOS( 10, "bios10", "epr-21577e (USA)" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 10, "epr-21577e.bin",  0x000000, 0x200000, CRC(cf36e97b) SHA1(b085305982e7572e58b03a9d35f17ae319c3bbc6) ) \
+	ROM_SYSTEM_BIOS( 11, "bios11", "epr-21577d (USA)" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 11, "epr-21577d.bin",  0x000000, 0x200000, CRC(60ddcbbe) SHA1(58b15096d269d6df617ca1810b66b47deb184958) ) \
+	ROM_SYSTEM_BIOS( 12, "bios12", "Naomi Dev BIOS" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 12,  "dcnaodev.bios", 0x000000, 0x080000, CRC(7a50fab9) SHA1(ef79f448e0bf735d1264ad4f051d24178822110f) ) /* This one comes from a dev / beta board. The eprom was a 27C4096 */
 
 // bios for House of the Dead 2
 #define HOTD2_BIOS \
@@ -1677,10 +1680,12 @@ Scan ROM for the text string "LOADING TEST MODE NOW" back up four (4) bytes for
 	ROM_LOAD16_WORD_SWAP_BIOS( 4, "epr-21578e.bin",  0x000000, 0x200000, CRC(087f09a3) SHA1(0418eb2cf9766f0b1b874a4e92528779e22c0a4a) ) \
 	ROM_SYSTEM_BIOS( 5, "bios5", "epr-21578d (Export)" ) \
 	ROM_LOAD16_WORD_SWAP_BIOS( 5, "epr-21578d.bin",  0x000000, 0x200000, CRC(dfd5f42a) SHA1(614a0db4743a5e5a206190d6786ade24325afbfd) ) \
-	ROM_SYSTEM_BIOS( 6, "bios6", "epr-21577e (USA)" ) \
-	ROM_LOAD16_WORD_SWAP_BIOS( 6, "epr-21577e.bin",  0x000000, 0x200000, CRC(cf36e97b) SHA1(b085305982e7572e58b03a9d35f17ae319c3bbc6) ) \
-	ROM_SYSTEM_BIOS( 7, "bios7", "epr-21577d (USA)" ) \
-	ROM_LOAD16_WORD_SWAP_BIOS( 7, "epr-21577d.bin",  0x000000, 0x200000, CRC(60ddcbbe) SHA1(58b15096d269d6df617ca1810b66b47deb184958) ) \
+	ROM_SYSTEM_BIOS( 6, "bios6", "epr-21577g (USA)" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 6, "epr-21577g.bin",  0x000000, 0x200000, CRC(25f64af7) SHA1(99f9e6cc0642319bd2da492611220540add573e8) ) \
+	ROM_SYSTEM_BIOS( 7, "bios7", "epr-21577e (USA)" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 7, "epr-21577e.bin",  0x000000, 0x200000, CRC(cf36e97b) SHA1(b085305982e7572e58b03a9d35f17ae319c3bbc6) ) \
+	ROM_SYSTEM_BIOS( 8, "bios8", "epr-21577d (USA)" ) \
+	ROM_LOAD16_WORD_SWAP_BIOS( 8, "epr-21577d.bin",  0x000000, 0x200000, CRC(60ddcbbe) SHA1(58b15096d269d6df617ca1810b66b47deb184958) ) \
 	ROM_REGION( 0x200000, "user2", 0) \
 	ROM_LOAD16_WORD_SWAP( "fpr-23489c.ic14", 0x000000, 0x200000, CRC(bc38bea1) SHA1(b36fcc6902f397d9749e9d02de1bbb7a5e29d468) ) \