PCs vs. Mainframes essays

PC's vs. Mainframes essays This paper will give a detailed comparison and contrast between Personal Computers (PCs) and mainframes. The first obvious difference between a PC and a mainframe is their size. A PC is about 18" square and maybe 8" wide. Most people could take one apart with little or no training and install a new component like a modem or sound card. You can buy a PC at most computer stores for less than $1500 and have a relatively powerful machine. In contrast, mainframes are very large and very expensive, and you would not be able to open one up and simply add new components. They are usually installed in temperature-controlled rooms with access being limited to authorized personnel. Maintenance is usually carried out by a third-party under strict contracts. A typical PC will have one processor running at about 2.6 GHz, a hard drive with 80 Gigabytes of disk space, and 256 to 512 MB of RAM. Mainframes on the other hand, can come with hundreds of hard drives in a sophisticated RAID array with 30+ Terabytes of storage capacity and typically mainframes will have multiple processors and gigabytes of memory. Most PCs will run a Windows operating system and function as clients in a network environment while mainframes exist only as servers and typically run some form of UNIX or Linux. There are a lot of variables when comparing the differences between PC's and mainframes, some of which include performance, reliability, and cost. In terms of raw CPU speed, there is probably not as big a difference as their once was. The differences lie mainly in reliability and I/O capabilities. Mainframes have a much larger I/O bandwidth than PC's have. Mainframe's have a lot of redundancy and serviceability features built in. The way they handle I/O is also much more efficient than the low-end PC boxes. Instead of one pathway into memory as in a PC, there are multiple memory banks providing multiple ports into memory. For example, Hitachi's Skylines have 16 po...