N64 Console with unique shell & unknown board serial number.

Yep that is the one, a Sega Saturn placed below the N64 prototype. I found interesting that the 1995 prototype had no heatsink mounts (EMI not important - Faraday cage), fiducial marks around CPU and RCP, a blue thermocouple just above the clock generator, (if not random dots or image artifacts) the top side has vias above the controller patterns - probably top side controller mounting just like in the E7I.

Nice to see how the U64 or N64 hardware layout evolved into its commercial form.

 

Here is the picture of the entire backside of the board with two close ups. I spoke with my brother and he said he used to have the matching jump pak cover for this but it is now lost Also he told me he bought it in a large lot of games from a gentleman who purchased it in a wholesale lot from bresoftware. I was thinking of calling them to see where they normally get their systems. It is a shot in the dark but it may shed some light on the history. Let me know if the picture comes through. thanks again guys!

 

Indeed, there are no heat sink mounts present on the 95 prototype. Beside the rather small changes you've mentioned the overall chip layout seems to be the final one - except for the rotated PIF. What do you meen by top side controller mounting on the E7I? Do you mean the traces leading to the controller ports? In fact these traces look similar between the 95 prototype and the E7I

Too bad that the cover got lost but thanks for those pictures! Here is a little comparasion between the E7I and the 01 retail rev I've made:



There are really some small differences like the traces to the controller ports, different holes under the CPU and RCP, missing solder pads for some caps... but the chips are all final.

Spoiler: click for marked differences

Absolutely! It would be totally awesome to be able to compare the E7I to the 95 proto but unfortunately the image quality is far to low. Anyway with those bits that are recognizable we can see quite a bit of how it evolved over the time