Operate software. The more powerful your CPU, the more kinds of applications you'll be able to run on your system. Software packaging always tells you the minimum amount of processing power you'll need to use that program. If you don't have enough power in your CPU, the software will run slowly or improperly.

Speed your computer's operation. A top-of-the-line CPU will perform tasks more quickly than an older processor. The difference in speed can be astonishing, especially when doing jobs that require heavy number crunching.

Do high-end design work. If you are working with graphics or computer-assisted design, a modern, powerful CPU is essential to manipulate the massive amounts of information found in complex and memory-intensive graphics.

Stay ahead of software design. Software development typically has lagged behind processing power. So it usually takes a while before popular software starts to demand more power than CPUs can deliver. Software developers have traditionally stayed behind this curve because they want to sell products that can be used on older machines. But so many new PCs are being sold every year that developers increasingly are able to make a profit on titles that require heavy-duty CPUs.