[nickpsecurity]

That's a good point but underselling it. My favorite thing about them was doing a single, system image that removed bottlenecks and complexity for developer at the same time. The PC's were using slow or redundant buses to connect high-speed components. SGI removed redundancies, used fast interconnects (GB/s), made them low-latency (microseconds vs milliseconds), and NUMA-enabled them. The last part meant that sending data to nodes didn't take middleware like MPI: you might just do a load and store instruction like on single node. Hardware took care of communications with cache-coherency. You did have to design for good locality to minimize moving data across nodes, though.

Add the other features like reliability (esp hot-swapping), servicability, and security (Trusted IRIX) to have some incredible machines. I always wanted inexpensive hardware with hot-swap, RAID, and something like NUMAlink connecting it. Never quite got that. One company did make a NUMA for AMD and Intel:

https://www.numascale.com/Scale-up-products/

[tachyonbeam]

I guess that's the difference between a workstation that's designed for performance and versatility before cost, and a PC, which is made to be affordable first. When the PC industry started, it was very much about repurposing whatever low-cost CPUs and off-the-shelf components were available, and finding ways of packaging this into a semi-usable machine for less than $1000. Things have changed quite a bit since, but much of the do-it-cheap rushed-to-market type of compromises are still with us.

[kragen]

Sure, the PCs that started the PC industry — things like the Apple I and the MITS Altair — were indeed "about repurposing whatever low-cost CPUs and off-the-shelf components were available, and finding ways of packaging this into a semi-usable machine for less than $1000." But, long before 1993, most CPUs and components used in PCs were being produced specifically for PCs, with uses in things like lab equipment, industrial control, and workstations a rather smaller secondary market.