Yeah, 32 bit windows can only address at maximum something like 3.5 GB of ram. Frankly, that's not really enough these days, which seems pretty crazy when I think back to my first 486 that came with a 100 MB hard disk and maybe 8 or 16 MB of RAM...
And 20 years from now 8-16gb is going to seem like 8 to 16mb.
The 486 was also on the order of 50-100mhz, and even cell phones today are not only exceeding 2ghz, but also running 2-4 cores.
edit: And in 20 years 2-4 cores is going to seem pretty small. Unless a whole new underlying hardware architecture is developed though, it's unlikely we'll see a 2-3 order of magnitude increase in processing speeds, though I wouldn't say it's an impossibility.