Fire Damaged Amstrad GX4000: Does It Work?

Two Amstrad GX4000 consoles, one simple question: does it work? The first is a lovely semi-boxed GX4000 with a gamepad and Burning Rubber, donated by Mike Dailly of Lemmings and GTA fame. The second is a melted monstrosity pulled from the damp remains of my house fire, after sitting in firefighting water for two weeks. You’d expect the clean one to boot and the burnt one to be dead. You’d be wrong. This video was sponsored by PCBWay.

This was the first episode of a mini-series called Does It Work: a no-nonsense format where I try a machine and, depending on the result, think about repair approaches and parts, or add-ons to make it more usable today, for a future video. No screwdrivers allowed (which, for me, is hard).

Mike Dailly’s GX4000: inspection

The box isn’t complete and the polystyrene inserts are broken, but the console inside is in really good condition. It comes with the ubiquitous Burning Rubber and, luckily, a gamepad, which is quite hard to come by now. Burning Rubber isn’t the most exciting game, but it’s fine for testing. There’s no power supply, though, which could be a harbinger of bad news.

Semi-boxed Amstrad GX4000 console with gamepad and Burning Rubber cartridge donated by Mike Dailly — Mike Dailly’s GX4000, with a gamepad and the ubiquitous Burning Rubber

The controller ports are on the front. Round the back are two power inputs side by side, 5V and 11V, with different-sized centre pins (I’m hoping nobody ever forced the wrong plug in), plus a SCART socket. With no SCART cable to hand I used a poor-quality SCART adapter into my LCD bench monitor (it has lots of handy inputs). In place of the missing PSU I used an adapter putting out 12V DC at around 5A. The console says 11V, but the 7805 regulator inside is good for up to around 28V, so that’s fine.

Does the clean GX4000 work?

First lesson: you can’t insert a cartridge unless the power switch is off, because the switch unlocks the slot flaps. On power up, the LEDs on both the console and the power supply blinked rhythmically, suggesting something was pulling the 12V down below the roughly 3V the LED needs. Then it suddenly stopped, just as my thumb touched the power supply (I think coincidentally), and we had a video signal. But Burning Rubber didn’t boot.

A good wiggle in the slot (many problems are solved with a wiggle in a slot) gave a solid green LED, but still no dice. Booting with no cartridge gave a weird video signal, so something is coming out of the video encoder. I don’t have much GX4000 experience, but the LED behaviour and the clean slot suggest a power problem to me. This isn’t a fixing video, though, so it goes on the shelf for later.

Clean Amstrad GX4000 console with a solid green power LED connected to an LCD bench monitor, failing to boot Burning Rubber — Solid green LED, but Burning Rubber won’t boot on the clean console

The fire and water damaged GX4000

Gloves on for this one: I don’t like handling anything covered in soot. When I lost my house, this console was at ground zero and was only saved because it was under a plastic box. It went through the fire, got doused by the firefighters’ hoses, and then sat in that water for two weeks before I pulled it out.

It’s disgusting. The cable is fused to the console, and its metal contacts hint at the damage that’s probably happened inside. The front controller port has drooped so badly that no controller will ever go in. The ports at the back are mysteriously intact, if dirty, but the cartridge slot is filthy. The power switch is fused in the on position, as the internal safety catch looks to have melted, and the metal Amstrad badge was hanging off, so I pulled it away.

Melted and soot-covered Amstrad GX4000 console from a house fire with its cable fused to the case — This GX4000 was at ground zero, then sat in firefighting water for two weeks

Switching on a fire damaged console

I’m not stupid enough to plug this in and expect it to work. Or am I? Incredibly, the LED lit (whether fully or dimly is hard to tell). With no cartridge: nothing on screen, which didn’t surprise me. So in went Burning Rubber, and the console booted. It even played music.

The picture isn’t great. It’s not the SCART adapter: we only seem to be getting the blue channel and the brightness information. That could be a failed component, corrosion from sitting wet for so long, or soot that has settled on the board, which is carbon-rich and can be both corrosive and conductive.

Fire and water damaged Amstrad GX4000 booting Burning Rubber with only the blue channel and brightness showing on the monitor — The burnt console boots Burning Rubber, with only blue and brightness coming through

So, does it work?

It’s a topsy-turvy world. The beautiful, clean console doesn’t boot a game. The one that sat in water after a house fire, so disgusting I don’t want to touch it, partially works, which means its ASIC is intact. On the clean one, I wonder whether a component was dragging the supply down (hence the pulsing LEDs) and then failed, which would need a look inside. On the burnt one, the fact that it produces any picture and sound at all is amazing to me.

There’s one more thing I really wanted to try after this: I’d heard you can make replica GX4000 cartridges without the protection chip, and with the homebrew that’s become available that sounded like a lot of fun. That became my follow-up video, building a GX4000 cartridge from all new parts using another, working GX4000 on loan. A later Does It Work episode featured my fire and water damaged Amiga A600 motherboard.

More from the Amstrad GX4000 projects: Making an Amstrad GX4000 Cartridge Without an ACID Chip: All New Parts.

More Amstrad on the site: an Amstrad CPC 464 found in the woods and part 2. For another fire survivor, see restoring a soot-damaged Intellivision.