diff --git a/src/mame/drivers/ymmu100.cpp b/src/mame/drivers/ymmu100.cpp
index 7aa1ba22e14..686dc3e0086 100644
--- a/src/mame/drivers/ymmu100.cpp
+++ b/src/mame/drivers/ymmu100.cpp
@@ -742,7 +742,7 @@ ROM_START( mu100 )
 	ROM_LOAD32_WORD( "sx743b0.ic35", 0x0000002, 0x400000, CRC(a9109a6c) SHA1(a67bb49378a38a2d809bd717d286e18bc6496db0) )
 	ROM_LOAD32_WORD( "xt445a0-828.ic36", 0x0800000, 0x200000, CRC(225c2280) SHA1(23b5e046fd2e2ac01af3e6dc6357c5c6547b286b) )
 	ROM_LOAD32_WORD( "xt461a0-829.ic37", 0x0800002, 0x200000, CRC(a1d138a3) SHA1(46a7a7225cd7e1818ba551325d2af5ac1bf5b2bf) )
-	ROM_LOAD32_WORD( "xt462a0.ic39", 0x1000000, 0x400000, CRC(cbf037da) SHA1(37449e741243305de38cb913b17041942ad334cd) BAD_DUMP) // Bit 12 fixed to 1
+	ROM_LOAD32_WORD( "xt462a0.ic39", 0x1000000, 0x400000, CRC(2ea5fce7) SHA1(134ad1a83578de9e1caa4853ebbf2635969dc88d) )
 	ROM_LOAD32_WORD( "xt463a0.ic38", 0x1000002, 0x400000, CRC(cce5f8d3) SHA1(bdca8c5158f452f2b5535c7d658c9b22c6d66048) )
 ROM_END
 
@@ -761,7 +761,7 @@ ROM_START( mu100r )
 	ROM_LOAD32_WORD( "sx743b0.ic35", 0x000002, 0x400000, CRC(a9109a6c) SHA1(a67bb49378a38a2d809bd717d286e18bc6496db0) )
 	ROM_LOAD32_WORD( "xt445a0-828.ic36", 0x800000, 0x200000, CRC(225c2280) SHA1(23b5e046fd2e2ac01af3e6dc6357c5c6547b286b) )
 	ROM_LOAD32_WORD( "xt461a0-829.ic37", 0x800002, 0x200000, CRC(a1d138a3) SHA1(46a7a7225cd7e1818ba551325d2af5ac1bf5b2bf) )
-	ROM_LOAD32_WORD( "xt462a0.ic39", 0x1000000, 0x400000, CRC(cbf037da) SHA1(37449e741243305de38cb913b17041942ad334cd) BAD_DUMP) // Bit 12 fixed to 1
+	ROM_LOAD32_WORD( "xt462a0.ic39", 0x1000000, 0x400000, CRC(2ea5fce7) SHA1(134ad1a83578de9e1caa4853ebbf2635969dc88d) )
 	ROM_LOAD32_WORD( "xt463a0.ic38", 0x1000002, 0x400000, CRC(cce5f8d3) SHA1(bdca8c5158f452f2b5535c7d658c9b22c6d66048) )
 ROM_END
 
@@ -775,7 +775,7 @@ ROM_START( mu100b )
 	ROM_LOAD32_WORD( "sx743b0.ic35", 0x0000002, 0x400000, CRC(a9109a6c) SHA1(a67bb49378a38a2d809bd717d286e18bc6496db0) )
 	ROM_LOAD32_WORD( "xt445a0-828.ic36", 0x0800000, 0x200000, CRC(225c2280) SHA1(23b5e046fd2e2ac01af3e6dc6357c5c6547b286b) )
 	ROM_LOAD32_WORD( "xt461a0-829.ic37", 0x0800002, 0x200000, CRC(a1d138a3) SHA1(46a7a7225cd7e1818ba551325d2af5ac1bf5b2bf) )
-	ROM_LOAD32_WORD( "xt462a0.ic39", 0x1000000, 0x400000, CRC(cbf037da) SHA1(37449e741243305de38cb913b17041942ad334cd) BAD_DUMP) // Bit 12 fixed to 1
+	ROM_LOAD32_WORD( "xt462a0.ic39", 0x1000000, 0x400000, CRC(2ea5fce7) SHA1(134ad1a83578de9e1caa4853ebbf2635969dc88d) )
 	ROM_LOAD32_WORD( "xt463a0.ic38", 0x1000002, 0x400000, CRC(cce5f8d3) SHA1(bdca8c5158f452f2b5535c7d658c9b22c6d66048) )
 ROM_END