Talk:3DNow!

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I'd love to see: (1) some analysis of the usefulness of these extra instructions, perhaps compared to Intel's MMX instructions and their subsequent SSE instructions in the Pentium 3, or even compared to AltiVec, and (2) some analysis of whether the 3DNow! instructions were actually used by developers. I recall the suspicion was that 3DNow! was all hype and marketing. Tempshill 22:07, 1 Mar 2004 (UTC)

As far as I know Microsoft DirectX and mplayer heavily use 3DNow! when available. But since virtually all x86 processors now support SSE the interest in 3DNow! generally fades away.Zuxy

It says "However, 3DNow! instructions can generally be executed with a lower latency and throughput than SSE instructions." Does this mean lower latency AND lower throughput? This is unclear, especially as the contexts seem to present an advantage over SSE.

latency means how long it takes to perform 1 instruction; throughput means how long it takes to perform each subsequent instruction. so lower latency and lower throughput = quicker execution

[edit] Rumour or truth

Long time ago I've heard that when a program simply used MMX or x87 instructions, the processor is able to real-time change the code to use better and faster 3DNow! instructions without any application intervention or modification.

Is that real, or was only a rumour?

—Claunia 23:17, 27 August 2005 (UTC)

It's a rumor, I'm afraid. Recent x86 processors (newer than Pentium Pro and K6) translate x86 instructions into RISC-like micro-ops on the fly and schedule/execute these micro-ops, but there's no x87->3DNow! translation. Programs have to rewritten and recompiled to use 3DNow! instructions.Zuxy

[edit] 3dnow2?

I was running mplayer to watch a video on my linux ststem, and saw the following among its output MPlayer dev-SVN-rUNKNOWN-4.1.2 (C) 2000-2007 MPlayer Team
CPU: AMD Athlon(tm) 64 Processor 3200+ (Family: 15, Model: 12, Stepping: 0)
3DNowExt supported but disabled
CPUflags: MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 0 SSE: 1 SSE2: 1

Does anyone know anything about this 3DNow2 flag? --Pandora Xero 13:49, 5 September 2007 (UTC)