This article compares the relative performances from the user point of view of two typical opertions research algorithms implemented on an IBM PC microcomputer and on a CDC Cyber 6400 mainframe computer. The basis of comparison is the computation time expressed in CPU seconds. The first algorithm performs exclusively integer operations, while the second algorithm performs primarily real arithmetic and transcendental functions. For the integer algorithm the speed ratio is 2.14 or 2.65 depending on the accuracy of the PC, for the real algorithm the speed ratio is 3.6. In general, the speed ratio is approximately equal to 3 to 1, which is very favorable for the microcomputer, considering the availability of micro computers and the relative cost of CPU time on each machine.