3 ms·
> On one hand The IBM System/38 used 128 bit pointers in the 1970s, despite having a 48 bit physical address bus. And the original processor was 24 bits, then
by tuatoru 4y ago
> On one hand The IBM System/38 used 128 bit pointers in the 1970s, despite having a 48 bit physical address bus.
And the original processor was 24 bits, then it was upgraded to 36 bits (not a typo: 36 bits), and then to POWER 64 bits.
(When that last happened, it was re-badged AS/400. Later, marketing renamed the AS/400 to iSeries, and then to IBM i, without changing anything significant. Still uses Power CPUs, AFAIK).
For users, upgrades were a slightly longer than usual backup and restore.
What's the hard part here?