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3DNow! Logo as used with the K6-2

3DNow! designated by AMD , Centaur and Cyrix developed multimedia - instruction set , with the AMD K6-2 was introduced 1998th This extension made new commands possible directly in the hardware, which could significantly accelerate the processor in computationally intensive applications. However, these new commands could only develop their effect if they were also supported by the respective programs, but this has been since the introduction of 3DNow! the case only to a small extent, since the majority of software developers preferred to use the alternative development SSE from Intel after its introduction in 1999 . One advantage of the 3DNow! Extension compared to the SSE extension was, however, that two 32-bit floating point numbers could be stored in a 3DNow! Register and offset against each other with the appropriate commands, whereas this was not possible with SSE. This function was only submitted with SSE3 with the commands HADD / HSUB / ADDSUB.

3DNow! should, as the name already suggests, bring major speed advantages, especially in the area of ​​3D graphics, i.e. vector operations. While z. B. MMX only supports whole numbers, 3DNow! many commands are available for processing single-precision floating-point numbers .

This approach is much more developed in ASICs (where it originally comes from) as well as in the AltiVec units of PowerPC CPUs - or on today's graphics cards .

AMD recommends the use of 3DNow! no more. Before using these commands, programmers should therefore check their availability using the corresponding CPUID bit. On August 18, 2010, AMD announced that upcoming processors would no longer support 3DNow. Only the PREFETCH and PREFETCHW commands were retained. Processors of the AMD Fusion series were then also the first AMD processors in which the instruction set extension was no longer required.

CPUs with 3DNow!

Since 3DNow! was one of the first additions to the x86 architecture, many CPUs (except from Intel) supported 3DNow! for years. A full list of all CPUs with 3DNow! would be very confusing. Reference should therefore be made to the list of microprocessors at this point .

Below is an overview of the CPU families in which the respective manufacturers 3DNow! have integrated:

Web links

Individual evidence

  1. AMD64 Architecture Programmer's Manual Volume 5 (English; PDF) - Appendix A: Recommended Substitutions for 3DNow! Instructions, March 2012
  2. 3DNow! Instructions are Being Deprecated (English)