Accurate Emulation

It ain't easy:

Honestly, even with all of the issues listed above, we've only scratched the surface of accurate emulation. Take the case of DICE, the digital integrated circuit emulator. Here is an emulator that works at the transistor level for absolutely perfect recreation of the very first video games ever created. To run Pong at about 5-10fps, DICE requires a 3GHz processor. Yes, you read that right: no computer processor at this time that can run Pong at the circuit level at full speed. It's not that DICE is a slow program; indeed, it is very well optimized. It's that there is enormous overhead to simulating every last transitor propagation delay.