I came across this interview with John Carmack recently while reading about the history of the Atari Jaguar. It's a console only a contrarian could love. But apparently, there were some unnecessary bottlenecks in the design which, if corrected, would have sped up peformance considerably:
Carmack's prescription? Replace the 68k with another 32 bit RISC, add dynamic cache to it and give the blitter at least a small buffer. He claimed that with these changes, the Jaguar would not have matched the performance of PS1 or Saturn but would have been "competitive":
"If the Jaguar had dumped the 68k and offered a dynamic cache on the risc processors and had a tiny bit of buffering on the blitter, it could have put up a reasonable fight against Sony."
Between Jaguar Wolf3D and Jaguar Doom he had mostly praise for the Jaguar's hardware. However his attitude changed as the project chugged along. After completing JagDoom, months of struggling to work around poorly thought out aspects of the system's architecture seems to have soured him to it somewhat:
"The Jaguar was definitely significantly hampered by its technical flaws, which kept me from ever being too big of a Jaguar booster. I was proud of my work on Wolf and DOOM (more so than just about any of the other console work Id has been involved in until just recently), but in the end, the better consoles won the war."
"The little risc engined were decent processors. I was surprised that they didn't use off the shelf designs, but they basically worked ok. They had some design hazards (write after write) that didn't get fixed, but the only thing truly wrong with them was that they had scratchpad memory instead of caches, and couldn't execute code from main memory. I had to chunk the DOOM renderer into nine sequentially loaded overlays to get it working (with hindsight, I would have done it differently in about
three...)."
It's a shame he didn't continue working with it. Reportedly he tried to get a stripped down port of Quake running on it for a while, though given what a technical marvel even the Sega Saturn version of Quake is, I struggle to imagine how it could be made to run on the Jaguar.
The sort of 3D we could have expected to see on the Jaguar, with the changes John Carmack recommended, would have been roughly the same as what we saw on the Gameboy Advance near the end of its lifespan.
Other game devs who worked on the Jaguar take a slightly rosier view of it than Carmack:
"Skilled programmer Steven Scavone, key member of 3D Stooges which released Gorf, still develops for Jaguar. Comparing it to systems he’s worked on, Scavone elaborated on tech-specs, also explaining in laymen’s terms. “It should be coded in as much assembler as possible. This machine flies when fuelled by assembler. The RISCs in proper concert with the 68k will do some absolutely amazing graphics. The Jaguar could [utterly] crush any 2D system. It’s a lot easier to program 2D for than the PSX or N64. You can thank the Tramiels for it being ‘underpowered’. The chips were not complete and had bugs. The designers, who weren’t experts in silicon design, missed fundamentals. Just one more register and [it could have run without stalling all the time]! If they [had fixed this], the Jag would have blown away the PSX. Later 3D titles like Battlesphere proved that systems at the time were no match for it.”
Curious what a "fixed" Jaguar would look like? That's essentially what the Jaguar 2, codenamed "Midsummer" was. The Jaguar but with the major glaring architectural mistakes corrected, and with faster clockspeeds on all processors:
The full leaked technical specifications can be read here. Atari was jumping the gun just a bit given that the Jaguar was on its last legs. But then, this is also when they released the CD addon. Like Sega, their solution to sagging sales numbers was to put out more hardware instead of more (and better) games.
3DO also tried this with their M2 prototypes which of course never made it to market. Just goes to show that trying to push out a successor to a failed console right away amounts to running away from your problems, which works about as poorly in business as it does in every other area of life.