A-Hackers-Guide
Sega Genesis

Identifying your model

Identifying Your Model

Knowing your exact model and board revision shapes every decision that follows, from RGB quality to how a region mod is wired. Spend a few minutes here before ordering anything.

Start with the case

  • Model 1 — The large original unit. Earliest versions have a high-quality video output and, on some, a wide cartridge slot.
  • Model 2 — A smaller, rounded redesign. Very common and inexpensive.
  • Model 3 — The smallest official Sega revision, with no expansion port and mono audio.

Then check the board

The case style only gets you part way. Open the console and find the VA number silk-screened on the mainboard. Different VA revisions of the same model can differ in audio mixing and RGB cleanliness, which matters for both video mods and region mods.

CluePoints to
Big boxy shell, large cart slotEarly Model 1
Rounded compact shellModel 2
Tiny shell, no top expansion portModel 3

Write it down

Note both the model and the VA number before closing the console. When you follow a wiring guide later, that revision detail tells you which diagram applies to your unit.