[quotemsg=20952754,0,1749524]Even more, in the case of the x86 architecture, it supports an 80bit extended precision floating point unit in hardware.[/quotemsg]
Ah, sad but true. Support for this exists in the x87 FPU, but not in SSE or AVX. I thought I ran across 128-bit float or int support, in some iteration of SSE or maybe AVX, but I'm not finding it.
The other thing that x87 had was hardware support for denormals. If you enable denormal support in SSE (and presumably AVX), it uses software emulation and is vastly slower. Also, x87 had instructions for transcendental and power functions.
Lastly, sort of one cool thing about x87 is that it's stack based - like a RPN calculator. I think that's one of the reasons it got pushed aside by SSE - that it's probably not good for pipelined, superscalar, out-of-order execution. But, still kinda cool.
If you're fond of over-designed, antique machinery, the nearly 4 decade-old 8087 is probably a good example.