Perhaps, but I don't think AMD was even considering SSE at that time, being so faithful to 3dNOW. At the time, it had some boosts in games like Quake 2, so AMD had no intent to consider the competitor's extensions. I'd say they began thinking when they reached 0.18m, if not at 1GHZ.
I have to fully agree with you Eden. In fact, I'd take it one step further.
When the P4 first came out, everyone laughed at how it practically relied upon SSE2 just to make up for Willy's design flaws. AND fanboys had field days with Intel believers, saying how almost <i>no</i> software had SSE2 support and so for 'real' applications, AMD kicked Intel's arse.
I think AMD itself was part of that mentality. I think the folks at AMD <i>purposefully</i> avoided giving any support to SSE2 for as long as they possibly could <i>just</i> so that SSE2-optimized apps would be few and far between.
Only now, they're not. It's a pretty common thing and easy to do with an Intel compiler. SSE2 has most definately caught on. And so, AMD finally releases (or at least will soon release) a core with it in.
I don't think that it had anything to do with taking time to implement. I think that it had everything to do with AMD wanting to give software developers as little reason as possible to optimize for SSE and later SSE2 because AMD believed that 3DNOW was better and especially when it came to SSE2, so long as software wasn't optimized for SSE2 the Athlon stood up very well against a P4.
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