Compare and Contrast PCS and Mainframes

Personal Computers and Mainframes: Comparison Ah, yes...the good, old mainframe. Although the days of whirring giant cabinets in the Six Million Dollar Man, or even the out of control "WHOPPER" computer in the classic cold war movie, War Games, have largely gone the way of the dinosaur, the mainframe computer is still in use today. Although the PC has become the modern definition of "the computer," both forms of the technology have specific uses, advantages and disadvantages.

In the early 1980's, the business world in particular was embracing computer technology at a rapid pace. Other technologies, including microfilm, microfiche, and hard copy records and documents began to be phased out by the mainframe. Indeed, companies quickly became aware of the tremendous power the mainframe computer could bring to their management of data and records (Bennett, 2000), and set up systems at individual "work stations," allowing access to the information in the mainframe. One major drawback to the widespread use of the large mainframe, however, was the immense cost.

To be sure, the early mainframe computers were significantly more powerful and useful than the first "mini-computers," however, their high cost and complexity made their implementation prohibitive for small companies and individuals. However, when the first "fast" processor was developed for mini and mid-range computers (the Pentium), it became quickly apparent that the mainframe stood to lose much of its appeal.

Of course, the biggest draw for companies (and individuals for that matter), is a good "bang for your buck," and acquiring computers that fit into this category became of primary importance in the late 1980's and 1990's (continuing into the 2000's). Not only were PC's proving that they could do almost everything that the larger mainframes could do, but at a significantly lower cost. In addition, mainframes took another hit in popularity when it became apparent that individual computers could be linked to each other via servers.

However, although many began to see the influence of the mainframe on the decline, there remained a significant gap in higher-end computing power between the mainframe and the PC that could not be bridged. Indeed, the average mainframe in use today can complete one billion instructions/second, while the average PC can only handle approximately 500 million (and the desktop, only three million).

However, after one reaches a certain point in speed (especially in consideration of today's PC processors), in many industries higher end functioning is a wasted capability -- much in the way a sports car capable of doing 200 mph is of little use to a grandmother who only gets behind the wheel to go to the local grocery and back. However, there are legitimate uses for the higher mainframe power, especially when a company or institution needs to support hundreds or thousands of users at the same time.

Further, according to Nadel and Katnic in their article, "Is the Mainframe Just a High Performance PC?" The difference lies mainly in reliability and I/O capabilities, built in redundancy and serviceability. Not only does this make the mainframe more useful in a high demand environment, but, according to Nadel, mainframes are more reliable (software and hardware).

In addition to the advantages of a mainframe regarding reliability and speed is something known as "parallel sysplex." Parallel sysplex is a way of writing serial code that can work across more than one mainframe. (Katnic, 2000). Again, this may not be useful for all purposes, but in those industries that demand more functionality in their computer power, the mainframe continues to tower over the PC.

Although many would have thought that the mainframe would be long gone at this stage of the game (indeed, many predicted its demise with the first Pentium), the mainframe continues to have a significant role in high-demand applications. There is absolutely no comparison between the speed of the average PC and the speed of a (working) mainframe. However, this capability is not required in all situations.

To be sure, the PC has its very important place in modern computing -- particularly because of its growing (exponentially) capability, speed and capacity, as well as due to its relative low cost and accessibility for the average individual -- after all, one would not like to park a mainframe in one's home office, even if one.