Bit ratings for consoles largely fell by the wayside after the 32-bit era. The number of "bits" cited in console names referred to the CPU word size, but there was little to be gained from increasing the word size much beyond 32-bits; performance depended on other factors, such as processor speed, graphics processor speed, bandwidth, and memory size.
The Sega Dreamcast was 32-bit and the last video game console to base its marketing on the bit/byte system. It has a dual-issue 32-bit CPU core, 64-bit GPU, and 64-bit data bus although the geometry sub-processor GPU can perform internal math on 128-bit words. PlayStation 2's CPU is known as the “128-bit Emotion Engine” but has a dual-issue 64-bit core. The Microsoft Xbox, which is also more powerful than the PS2, uses a 32-bit CPU and 256-bit GPU. To take the usage to absurdity, one memory bus on the PS2 is 2,560 bits wide. The importance of the number of bits in the modern console gaming market has thus decreased due to the use of components that process data in varying word sizes. It is also important to note that most game companies sell on “n-bit talk” to over-emphasize the hardware capabilities of their system. The Sega Dreamcast and the PlayStation 2 were the last systems to use the term “128-bit” in their marketing to describe their capability
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