[to11mtm]

Yeah, but RDRAM gave them one big benefit: Even with the price premium of RDRAM back then, it was the cheapest route to getting 500mb/sec of memory bandwidth.

The Playstation by comparison used EDO (Based on eyeballing the pictures on wikipedia, baseline was 70ns/60ns for CPU and Video memory.) But, It's main bus was under 133mb/sec, and the fastest it could read from CD was 300kb/sec.

EDO Memory would have kneecapped the N64 from a memory bandwidth standpoint. The cartridge bus alone is over 200mb/sec. SDRAM -might- have done the job but may have wound up being more expensive; PC-66 (we are at the infancy of SDR in 1996) would have meant a PCB with 8 chips laid out for the parallel bus. To be frank I'm not sure Nintendo could have even gotten such a configuration (i.e. 8 512KB PC-66 chips.)

RDRAM was definitely a design compromise, but in retrospect I understand it's use in keeping overall costs down.

Dedicated video ram would have been a better option however, but I think it was another cost issue.

[mng2]

It's interesting to consider the N64 in contrast to the first Voodoo card. One is a console and the other is an add-in card, but both launched in 1996, with underlying 3D technology from SGI. The Voodoo used EDO RAM, 8 chips of 256k x 16b, 2 MB for the z+framebuffer and 2 MB for the texture memory. With 50 MHz EDO RAM, wired in a 64-bit bus, the peak texture bandwidth would be 400 MB/s, dedicated to that purpose alone; in contrast the N64 RDRAM was main memory and had to service other functions.

The N64 launched at $200, the Voodoo at $300. Of course you would additionally need a computer to run the Voodoo, but I remember thinking the N64 was already way too expensive back in the day. It would've been even more expensive to support a 64-bit memory bus.