Originally Posted by
Chilly Willy
RDP >> VDP1
RSP > VDP2
So yeah, I'd say the N64 could have matched anything the Saturn could have done at it's very best. There's actually nothing magic about the RCP at all, despite all the rhetoric from SGI and Nintendo. It's a simple 32-bit MIPS core (missing multiply and divide instructions) with 4KB of local ram for instructions, and 4KB of local ram for data, paired with a nice block DMA channel, a nice vector unit, and a really nice 3D GPU. The vector unit is optimized towards 3D math and also multi-pixel manipulation. The DMA is geared towards rapid fetch and store of blocks of pixels or geometry data. Running the MIPS core from local ram means it runs all instructions at the full clock rate of the RCP.
SGI/Nintendo's "microcode" was nothing more than a list of commands you put into ram that the RSP MIPS core then DMA'd into it's local ram to execute like interpreted languages. That's why the "microcode" could be changed - it's not really microcode, but an interpreted language with the interpreter loaded into the RSP instruction ram. SGI/Nintendo tried to make the N64 look like Magic to impress people, but it's actually pretty simple once you get past all the bullshit marketing.