At the core of the DreamCast is a 200MHz Hitachi SH4 processor with 8KB of instruction and 16KB of data cache on chip. Serving it is 16MB of interleaved SDRAM running at 100MHz and connected by a 64-bit memory bus. The SH4 is 2-issue superscalar RISC processor designed with Windows CE and 3D in mind. It sports a 32-bit integer unit and a 64-bit floating point unit. It has a multiply-accumulate unit that, Sega tells us, can take four floating point numbers, multiply them by four, then sum them all in only seven floating point instructions. These kinds of abilities prove useful for 3D graphics calculations. In fact, in certain procedures, it can attain 1.4Gflops of processing power. Of course, such situations rarely, if ever, come up in the real world, but the processor's capabilities are still impressive and translate into high frame rates in complex game scenes.

While it isn't as versatile as a Pentium III or Athlon, the SH4 gives the DreamCast a strong heart that contributes to smooth frame rates and complex scenes. It also gives the DreamCast enough flexibility for it to run WindowsCE and power a software modem, tasks that elevate the DreamCast above being just another console.

The graphics system of the DreamCast is based around a 100MHz PowerVR 2DC, a version of the PowerVR Series 2 graphics chip designed specifically for the DreamCast. Serving the PowerVR 2DC is 8MB of 100MHz SDRAM. Doing the math gives you a fill-rate of 100M/pixels. What sets the PowerVR 2DC apart from most other graphics chips, in consoles and computers, is its method of drawing textures. It uses tile rendering, where each frame is broken down into many "tiles" rendered one at a time, and deferred texturing, where surface visibility is determined for each tile before texturing, lighting and shading, so those time consuming processes are only performed on visible surfaces. This drastically cuts the need for memory bandwidth, so that seemingly low fill-rate of 100M/pixels is not a problem for the DreamCast. Also, since the DreamCast is meant to be used with a TV, it doesn't have to support the fill rates needed to run at resolutions like 1024x768. If you would like to read more about deferred texturing and PowerVR's technology, please read our technology article on the PC version of the chip here. Sega told us that there are differences between the PC version and the DreamCast version of the video chip (beyond just clock speed 100MHz for DreamCast vs. 125MHz for PC), but the only difference they named was that the per-pixel lighting was unique to the DreamCast version.