Metal Slug 4 bug?

For those that have MS4 MVS, has it ever locked up on you? The one at work freezes hard every now and then, and it's ALWAYS at the same point. In the attract mode where the character is riding the bike, and they drive by the Metal Slug sign in the background and blow up a truck in front of it, the game freezes(requires hard reset). It doesn't always happen, just occasionally, but it's always at that point.

I haven't opened the cart, but I believe it's an original, as we specified original when we ordered it(distributer asked if we wanted original or boot ), and I have looked into the case vents to see if there were any EPROM chips, and I didn't see any. The cart also has a serial number on it.

This is running on a MV-2F board with an official SP-U2 BIOS chip in an original dedicated cab, with Metal Slug 1(official) in slot 2, and MS4 in slot 1.

Hello,

You might have to take it apart, when I bought a bootleg MS4, the bootleg chips were on the bottom second board & there was part of an old move sticker taped to the top of them to keep them form contacting the upper board. Although on the copy that I had didn't freeze up, just the sound was real crappy & the graphics around the characters & vehicles would not come in all the way. Luckily I sent it back & got a full refund. If you do take it apart, look for alot of unecessary wiring & soldering. Look at the date of the boards too, mine had '93 or '94 dates on them. I hope this helps. Laters...

Well, I checked it today...and I'm 99% sure it's legit. The ROM chips have 263-x on them, with Mega Enterprises stamped on it as well(mask ROM's, not EPROM). Seems weird that it would lock at the same spot from time to time...

These errors seem all to common now a days. One thing is clear, the quality control at Playmore is nowhere near the standards of SNK (looking at ROTD, Matrimelee (although minor in that case), etc). I don't have MS4, but... I am interested in:

1. What are you running it on, multi slot or single
2. If single which revision of the board
3. If multi, have you tried it in other slots and with out other games in the machine.

The 3rd is the most important, I have seen that some games can conflict with one another, MS1 for example, has trouble in a multislot with certain other games...

-Nick

The board is a MV-2F with SP-U2 BIOS chip. MS4 is in slot 1, and I've tried 2 games(MS1 and bust a move) and it happens with either one in slot 2. I haven't tried MS4 by itself though...

I did notice something odd though. When you first power on the system, it shows the old style BIOS logo(330 mega), the shows MS1 attract mode(even though it's in slot 2). It then shows MS4 attract, then MS1 again, then the new GigaPower logo, then attract mode for MS4 then MS1 loops.

The same happens with Bust a Move, but why would it run slot 2 first?

The BIOS will run all MEGA games before GIGA games, that is just the way it does it. It gets more confusing in the 4 and 6 slots, but that is normal operation.

The 2f is a pretty compatible board, it usually is less prone to problems (just in my experience), however, you may want to try the game in the 2 slot by itself and see if it does indeed lock up.

-Nick

I'll try it out next time Im at work.

If you can hear the sound, can you check to see if level 3 has static in the sound? It's minor but there...