The Mystery of the Power-Sucking Neo Geo Pocket Color

About two and a half years ago, I finally took the plunge on something I had been wanting for years: a Neo Geo Pocket Color. Or, more specifically, a special edition NGPC themed after the Hanshin Tigers, a Japanese baseball team that I like and follow.

I finally got my hands on one after years of watching eBay and I loved it. It was gorgeous and hit all kinds of pleasure centers in my brain. Retro video games, baseball, the Japanese language… Hell, it even came wrapped in newspaper with an article featuring Shohei Ohtani, a megastar in the Japanese baseball league who, at the time, was making his decision about who to play for in America.

There was just one problem… This was 90s tech. More specifically, it contained 90s-era non-backlit screen tech. I couldn’t see a damn thing unless I played it under a lamp. But you know what? In those times that I could see what I was doing, it was phenomenal.

At the same time, I also got myself a Neo Pocket Flash Masta flash cartridge to better explore the system’s library without completely draining my bank account. Even better, it was a way to play the English fan translation of SNK vs. Capcom: Card Fighters 2 on original hardware. Well, the flash cart worked, but I noticed something. Any time I played a game with it instead of an original cartridge, it seemed to really drain the batteries.

Supposedly, original NGPC hardware has 40 hours of battery life on two AA batteries. I was getting maybe three to four hours out of some Energizer NiMH rechargeables. I didn’t make much of it at the time and just assumed the Flash Masta drained batteries unusually fast. But between the screen issues and the battery draining, I just didn’t get much use out of the system. It went into my closet and mostly stayed there, until recently.

A full screen IPS mod finally became available for the NGPC and I knew I had to have one. I’d gotten pretty handy with hardware mods in the last couple of years, so it was the perfect project. I ordered up an IPS kit from eBay and a replacement shell from AliExpress (the screen replacement requires a physical modification, and I couldn’t be cutting up a collector’s item!). They arrived safely, and I set to work…

And it came out absolutely amazingly. The new screen is just stunning and I was sucked into the platform in a way that I simply wasn’t when I first bought it. Finally, I could see what I was playing! And the new screen showed how vibrant and colorful the games were truly meant to be.

Replacement Shell and IPS Screen Mod Kits
IPS Mod – Before and After

Then the battery problems started. Forty hour battery life? Yeah, right! We weren’t even talking four hours… It was more like two! But it was strange behavior. As the batteries were dying, the system didn’t just stop working. Instead, it would often power on to a point where the game was booting and there was sound, but the screen wouldn’t turn on. Or, the screen would turn on but it would boot to the system BIOS screen instead of the game. Oddly, if I put in an official cart instead of the flash cart, it would often boot fine and I’d get some substantial extra playtime out of it.

At first, I passed all this off as funky behavior because of power drain. But that left me disappointed and unsatisfied. Did I really do all that work for a system that would only give me a measly two hours of battery life? I wouldn’t be able to take it anywhere like that and might as well just play it at home, plugged in.

So I decided to investigate. I started with the obvious: maybe I connected something improperly during the mod. I opened it up and double checked the screen connections and solder points, but everything seemed fine. Then I got curious about the batteries. I pulled out my multimeter and checked the voltages on a pair of batteries that had just stopped working. These were a fresh set of NiMH batteries rated for 1.2 volts… But the “dead” batteries were reading over 1.3v when I tested them! What the hell? They had plenty of juice still left in them! A newly charged set was reading just over 1.4v, so the power in the pair I used had barely dropped.

Rechargeable NiMH voltage test – 1.35v is above the battery’s rating, but apparently not enough to power the NGPC!

And that’s when it struck me. The batteries weren’t dead, they just weren’t supplying enough power anymore for this specific combination of hardware. A typical alkaline AA battery is rated for 1.5v. Use two of them and you get 3v. As time goes on and the batteries start to drain, the voltage they’re capable of supplying will start to taper off. Usually, the device you’re using them in can tolerate those lower voltages and continue to operate for some time. In the NGPC’s case, its low power demands mean typical batteries last quite a while.

Typical rechargeables, however, are only rated for 1.2v. Use two of them and you’re getting 2.4v. At 2.4v, I’m already at a disadvantage from the start. Add a couple hours of drainage and the fact that the actual voltage under load during operation was likely lower, and apparently we were crossing a point of no return very quickly. It seems the IPS screen and Flash Masta are much more sensitive to voltage drops than the NGPC itself, which explains why the system would often power on without booting a game off the flash cart, or boot without turning on the screen.

So, in summary, the NGPC plus an IPS screen plus the Neo Flash Masta plus rechargeable batteries is a finicky combination. What’s the solution? Well, you could avoid rechargeable batteries and probably get some additional gaming time, but that’s an unsatisfying solution. What you really need is a better power supply: something that will provide a consistent 3v without premature voltage drops.

The obvious answer once I thought of it in those terms was to use lithium-ion batteries, since they do a much better job of maintaining their voltage over time than other types of batteries. One approach would be to mod in a rechargeable Li-ion battery pack into the NGPC, but that felt excessively complicated. Instead, I turned my attention to a relatively new type of battery I’d never used before – rechargeable Li-ion AAs!

These turned out to be the perfect solution. They’re slightly expensive at a little under $30 for a four pack, but proved to be well worth it. I haven’t timed it out, but they seem to power my system for a good 6-8 hours and recharge via USB in only 1.5 hours (compared to about 12 hours for my old NiMHs). Less battery life than original hardware, yes, but plenty for my needs. And the short charge time means a freshly charged set will be ready for me before the current set ever dies out.

So to all you NGPC fans, if you’re thinking about screen modding your system, keep power needs in mind. Especially if you’re using a flash cart, too!