mv1b

Picked up another MV1B, thought it was working fine however noticed some games didn't have audio, but some did and then with some experimentation found some games had slightly broken audio. For example, Xeno Crisis seemed to have all sounds, whereas not a peep out of Metal Slug and Garou was...

My MV1B has developed a Backup RAM unwriteable fault, it seemed to start after I cleared the Backup RAM and now it triggers on every boot. Popped the diag BIOS in and I get this: I assumed RAM4 is the upper chip and as I had a spare replacement TC55257DFL-85L chip from when I fixed the...

My MV1B has one of the NEO-BUF bypass "patches" on the slot PCB, (the one on the main PCB is still present). According to https://wiki.neogeodev.org/index.php?title=NEO-BUF bypassing one/both of these, (it doesn't state which and sort of implies there's only one, when there's actually two), can...

I recently built some of @ack's excellent Neo Geo diagnostic PCBs just as a useful thing to keep handy. Testing them out on my MV1B I wasn't expecting to have any issues. However the first time I tried them with the latest v0.19a02 diagnostic BIOS, I got a VRAM 32K error on power up which I...

Just received my MVS bought from good ol' Aliexpress! Not sure what I was expecting, but there was a few things notable about it. 1) The outer ABS plastic shell was scratched to hell and back. I removed it and scrubbed it down with soap, a toothbrush and melamine sponge to see if some of that...

I recently got an MVS and supergun setup and it worked perfectly for a few days, but one morning it started having this issue and it hasn't worked properly ever since. Regardless of how I have the hard dips set, the console will briefly display "WORK RAM TEST" as if all the switches are enabled...

Hello everyone, Question level beginner. I got a mv1b and I installed a battery holder on it, but saves are not working. I just took off the old battery and installed the holder, I didn't not remove anything I would like to use it with ml2032 not cr2032. I tested the electric tension on the...

Until recently my MV1B still had the original rechargeable battery. It looked a bit grotty but hadn't leaked however it wouldn't keep a charge for very long so I figured I should replace it pronto. I bought a Dreamcast battery kit as it looked like the correct lead layout but it was only when I...