This parallelism is separate from the parallelism provided by a superscalar processor; the eight values are processed in parallel even on a non-superscalar processor, and a superscalar processor may be able to perform multiple SIMD operations in parallel.
With a SIMD processor there are two improvements to this process.
For one the data is understood to be in blocks, and a number of values can be loaded all at once.
A modern supercomputer is almost always a cluster of MIMD machines, each of which implements (short-vector) SIMD instructions.
A modern desktop computer is often a multiprocessor MIMD machine where each processor can execute short-vector SIMD instructions.
Sun Microsystems introduced SIMD integer instructions in its "VIS" instruction set extensions in 1995, in its Ultra SPARC I microprocessor. The first widely deployed desktop SIMD was with Intel's MMX extensions to the x86 architecture in 1996.
This sparked the introduction of the much more powerful Alti Vec system in the Motorola Power PC's and IBM's POWER systems.The first era of modern SIMD machines was characterized by massively parallel processing-style supercomputers such as the Thinking Machines CM-1 and CM-2.These machines had many limited-functionality processors that would work in parallel.Vector processing was especially popularized by Cray in the 1970s and 1980s.Vector-processing architectures are now considered separate from SIMD machines, based on the fact that vector machines processed the vectors one word at a time through pipelined processors (though still based on a single instruction), whereas modern SIMD machines process all elements of the vector simultaneously.Instead of a series of instructions saying "retrieve this pixel, now retrieve the next pixel", a SIMD processor will have a single instruction that effectively says "retrieve n pixels" (where n is a number that varies from design to design).