K5

6/5/99

AMD K5 Processor: AMD's first Pentium level CPU was the K-5. It was an elegant design that executed Intel 80x8x instructions using a core base on the superscalar RISC AMD 29000 CPU. Unfortunately, the Intel Instruction set is quite complex and is not efficiently converted to RISC. As a result the K5 was rather slow compared to competing products at competing price points from Intel, Cyrix and NexGen. AMD eventually bought NexGen and based their next CPU -- the K6 -- largely on the NexGen Pentium Class CPU design.

Within limits, the K5 can process four instructions simultaneously in six dedicated pipelines (two integer, one FP, two memory access, one branch). It has a 16Kb internal L1 instruction cache and an 8KB internal data cache. It does not support MMX instructions. Integer performance was quite impressive, floating point performance, less so. The K5 was released in 1Jan96 P-rated as 100MHz. Subsequent releases were at 100MHz actual (133MHz P Rating) and 116.6MHz actual (166MHz P Rating). 75(75), 90(90) and a different 90(P rated 120) MHz versions were also released. All K-5s use a 296 pin "Socket 7" compatible package. Voltage was 3.3 volts. Power unknown.

Manual is available on line: https://www.amd.com/en -- download 18524.pdf