Re: Optimised in compiler
> AMD showed that you could have 64 bit CPUs which would still run legacy 32 bit code, so you didn't need to ditch everything to get 64 bit capabilities.
This is perhaps the biggest issue.
When the main part of DEC's Alpha dev team objected to being sold to Intel they upped sticks and moved en-masse to AMD with the result of them bringing out the AMD64 architecture. It could run the legacy x86 code so had a massive market place.
Intel had wanted x86 to die out, other people could make it. They'd hoped that IA64 would corner the market giving them a monopoly. There wasn't ever supposed to be an x86-64. But AMD and the Alpha design team forced their hand.
In the end they proved that it didn't matter how crap the instruction set was, what mattered was the market size as this controls the investment in research.
Intel had wanted to use that to drive Itanium, and this is why just about everyone in the business had signed up for Itanium initially. The expectation was that all the money was going to be thrown at IA64.
There were other issues too of course. The initial version of the chip, Merced which was designed at Intel was years late. The mark 2 processor, McKinley, which was designed at HP nearly over took it, as was detailed in stories here on El'Reg at the time. Merced ended up being little more that a developers platform.
But then AMD64 arrived and so many developers went off in that direction and took the market place and therefore the money with them. It doesn't matter how good your HW is without SW you can't sell any of it. I used to fill show stands with eager people demo'ing Unix workstations but when the buyers realised there were no apps do what they wanted they wondered off.
AMD64 allowed large flat memory models and so killed off the Unix workstation market place in a blink of an eye. Turns out it only existed because PCs had not been able to hold enough RAM to do many tasks. Linux could run most of the Unix apps with little or no tinkering. Lots of the dev teams for Unix apps already had their code running on Linux anyway as it was a free "yet another build platform" they could test their portability. Free to the extent it was often run on HW which was destined for the skip because it wouldn't run the latest version of Word on some admin's (not sys admin) desk.