unibus to modern disk interface?

discrete A Pentium 166 MMX chip, which was a common chip with mobility features used in some early Pentium-based laptops uses roughly 4.5M transistors. A little math (and this is all approximations and done conservatively) shows what might result. Such a CPU, using small-outline surface mount leadless transistors on 12x9 circuit boards with relatively tight design rules and multi-layer boards, would take something like 32 boards just for the transistors. Add in the overhead of other discrete components and you are looking at something like 81 boards (assuming roughly 2.5 discrete components per transistor). Not allowing any room for chassis, backplane, board spacing (for cooling), cooling, and interconnect, the CPU alone would a cube roughly 21 inches on a side. Add in overhead for the stuff listed, you'd probably be looking at a cube 2 feet on each side. The CPU by itself could probably be packed into some kind of backpack, but it'd be heavy. That's just for the CPU. Then you'd need RAM, ROM, IDE storage interface, keyboard interface, mouse interface, serial, parallel, floppy disk, a video subsystem, and LCD panel. Just the electronics for all of these things, assuming the use of ICs of the time rather than trying to make them all using discrete components, and it's my guess that the result would be too large and too heavy to carry...not even considering what it'd take to power the beast. If you tried to do everything with discrete components(except the hard disk and LCD display) -- well...it'd be more like something (a pure guess) like 12 or so 7-foot 19" datacenter racks full of boards, and the interconnect would be a real nightmare. Power distribution and cooling would be "interesting". Hardly laptop, much less "luggable".