Tips for Beginners
Choosing the right console
  Most older systems were released in two versions: the initial release, and a compact version. The most popular the compact versions was the Sega Genesis Model 2. Although these systems are lighter and more attractive because of their small, portable size, they can be difficult to modify or overclock.
   The Sega Genesis is a good example of this. The Genesis Model 1 had many features that the model 2 lacked. For example, my Genesis Model 1 has a Z80 reset switch mounted on it that resets the sound. If I had a Genesis model 2, this would not be possible, as the Z80 was incorporated into one large chip which housed many other chips.
Genesis model 1 (left) and model 2 (right)
   Another issue with the smaller consoles is stability when overclocking. The logic boards in the smaller models are usually cheaply made versions of the boards in the original models. For example: The Genesis model 1 is more stable when running at 13.4 MHz than a Genesis model 2. The model 2 tends to lock up probably due to the smaller amount of power it recieves and the cheaper materials used in manufacturing.
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   If you are shopping around for a system to overclock or use to discover new mods, don't let the small size of the  Genesis model 2 , mini SNES, PSOne, or any other sized-down version make your buying decision. Go for the original models, you will be a lot happier and less frustrated if you do!
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