Double Dragon PCB ROM 3 error

anotherit

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I have a Double Dragon board that I have been messing around with and I'm complete at a loss at the current moment. When I supply +5v to the board it will give a ROM 3 error on the screen at start up and then glitch out in a random fashion soon after. If I increase voltage to 5.8v the ROM 3 error will still be present but the game will run 90% of the time. Sometimes after running at the higher voltage for a while the ROM 3 error will go away completely.

I put a brand new power supply into the cab. Looking around the board nothing looks obviously broken but some ICs do seem to get very hot when running at 5v... any suggestions?
 
If you run a JAMMA board with Voltage greater than +5.25 Volts, you will start FRYING your Logic chips. Logic chips start to fry at +5.25V--just check their spec sheets.

D.D. should work fine with +5.00V~+5.10V of power. If it does NOT then you have a problem with either the PSU or the game board.
 
I don't have one in front of me so I can't tell you offhand which one to replace.
 
The voltage measured at the connector is only slightly higher than the voltage being read at each of the EPROMs at pin 28. The reading is consistent on all of the EPROMS as well...
 
I dumped the 4 ROMs and compared them with MAME and got the following results:

\mame>mame -romident badboard.zip
Identifying badboard.zip....
21a-4fromboard.bin = 21a-4_2 ddragonua Double Dragon (US set 2)
. = 21a-4_2 ddragonub Double Dragon (US set 3)
21a-1fromboard.bin = 21a-1_6.bin ddragonub Double Dragon (US set 3)
21a-2fromboard.bin = 21a-2_4 ddragonua Double Dragon (US set 2)
. = 21a-2_4 ddragonub Double Dragon (US set 3)
. = 21a-2-4.25 ddragonw1 Double Dragon (World set 2)
21a-3fromboard.bin = 21a-3.24 ddragonb Double Dragon (bootleg with HD6309)
. = 3.bin ddragonba Double Dragon (bootleg with M6803)
. = 21a-3.24 ddragonu Double Dragon (US set 1)
. = 21a-3 ddragonua Double Dragon (US set 2)
. = 21a-3 ddragonub Double Dragon (US set 3)
. = 21a-3.24 ddragonw Double Dragon (World set 1)
. = 21a-3.24 ddragonw1 Double Dragon (World set 2)

\mame>romcmp badboard.zip ddragonub.zip
4 and 4 files
21a-4fromboard.bin 21a-4_2 IDENTICAL
21a-1fromboard.bin 21a-1_6.bin IDENTICAL
21a-2fromboard.bin 21a-2_4 IDENTICAL
21a-3fromboard.bin 21a-3 IDENTICAL

Does that mean the chips have the proper programing but they are not working properly with the board? Would the best way to resolve this be to get a known working board and swap chips until I find the bad one?
 
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