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Dex wrote:I think if i am not mistaken, that EFI was originally created for Intel's IA-64 architecture, i think that AMD with there AMD64 new that you can not get rid of legacy.
And even M$ is learning http://apcmag.com/apc/v3.nsf/0/E666E4A0 ... 2C008166C4
Watch and learn gaf

M$ do not know what they have done. I guess that one hell of alot of M$ users will now either switch to Apple or Linux. I don't see why M$ are such a pain. They say one thing only to do the exact opposite.

Dex wrote:I think if i am not mistaken, that EFI was originally created for Intel's IA-64 architecture, i think that AMD with there AMD64 new that you can not get rid of legacy.

You're right that the lack of backwards compatibility was one of the more important reasons why the IA64 eventually failed. However EFI isn't part of IA64 and there's no reason why the new standard shouldn't be successful on regular x86 hardware. Apart from that the transition from PC BIOS to EFI would never cause as many problems with backwards compatability as a switch to IA64 could have meant. It's only drivers, bootloaders and the operating system that will be affected by the change. User applications wouldn't even notive that they're running on a different system.

Dex wrote:And even M$ is learning

"It will not be available in the release version of Windows Vista later this year – Microsoft says people will have to wait for an unspecified 'subsequent release of Windows client'."

I guess it now depends on the hardware manufacturers: If they'll include EFI support in their new products Microsoft won't have any other choice than upgrading Vista.

cheers,
gaf

Hi,

In general there's a major problem with anything new - people don't write software until people are using it, and people don't use it unless there's software for it. This applies to new OS's, new CPUs, new architectures, new BIOSs, etc. Backwards compatability solves this problem (but may create other problems).

gaf wrote:

Dex wrote:I think if i am not mistaken, that EFI was originally created for Intel's IA-64 architecture, i think that AMD with there AMD64 new that you can not get rid of legacy.

You're right that the lack of backwards compatibility was one of the more important reasons why the IA64 eventually failed. However EFI isn't part of IA64 and there's no reason why the new standard shouldn't be successful on regular x86 hardware. Apart from that the transition from PC BIOS to EFI would never cause as many problems with backwards compatability as a switch to IA64 could have meant. It's only drivers, bootloaders and the operating system that will be affected by the change. User applications wouldn't even notive that they're running on a different system.

It wasn't so much the lack of backwards compatability, it's more that the backwards compatability wasn't very good - the original Itanium did support the 80x86 instruction set, but it was insanely slow, and no-one wanted to pay high prices for slow 80x86. More recent Itanium CPUs dumped 80x86 compatability because Intel found it was faster to emulate 80x86 instead of including it in the CPU, but this meant you need an OS designed for Itanium to run the emulator. Microsoft had the OS to do it, but they mostly gave up on Itanium leaving it without any OS except for portable/free Unixes (Linux, etc) which could just as easily run on much cheaper hardware (including Intel's competitors).


Cheers,

Brendan