Building A SEGA Neptune In 2023

The Neptune, a console originally slated for release by Sega in 1995, never saw the light of day due to its cancellation, closely tied to the impending launch of the Sega Saturn. Essentially, the Neptune can be considered a fusion of the Genesis and the 32X. Despite Sega’s decision not to release the console officially, dedicated enthusiasts took matters into their own hands, giving rise to Neptune builds by modders such as Longhorn Engineer and Infidelity_NES.

These early Neptune builds were remarkable achievements, successfully combining a Model 2 Genesis motherboard and a 32X within the confines of a Model 2 Genesis housing. However, one couldn’t ignore the fact that these modified consoles still resembled a Genesis rather than the envisioned Neptune.

Enter Dan, also known as DIVIZX, who is a huge Sega enthusiast.  Dan was quite distraught that we never got a Neptune, so 27 years after the console’s announcement, Dan embarked on a journey to develop an authentic Neptune shell. His objective was clear – to create a faithful representation of the console shell, capable of accommodating a Neptune mod. To achieve this Dan collaborated closely with PCBAssembly99, assisted Dan by testing the fitment of the mod in his shell.  PCBAssembly also pioneered a new way of doing the Neptune mod dubbed the “modular” build. PCBAssembly99’s “modular” approach made the Neptune mod entirely reversible while also simplifying the installation process, eliminating the need to solder 64 individual wires to connect the Genesis directly to the 32X. He also used a triple bypass to further enhanced the mod.

Thanks to the collaborative efforts of Dan and PCBAssembly99, I was successfully able to complete a Sega Neptune mod that truly captures the essence of what the console might have been.

For those eager to embark on their own Neptune modding journey, Dan has a project page on PCBWay where you can order the complete shell. Additionally, PCBAssembly99 has created a comprehensive “How To” guide for building a “modular” Neptune on GBATemp, complete with a bill of materials necessary for the mod.

However, there are a couple of drawbacks to having a 32X “permanently” attached to your Genesis. Playing Sega CD games using Krikzz’s Mega Everdrive Pro is not possible, but fear not – connecting the Neptune to a regular Model 2 Sega CD allows you to enjoy these games the ol’ fashion way.

It’s worth noting that the buttons on the Neptune shell can be a bit finicky and may require some tinkering to get them to operate smoothly. Despite these minor inconveniences, the ability to construct a console that Sega never officially released is a testament to the remarkable capabilities of the retro modding community when they come together.

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