Buying a new computer

It is amazing how little relationship there is between price and performance now in the home-computer marketplace. A quick analysis of about 30 different PCs costing between $500 and $700 resulted in benchmark tests ranging from the high 500s to a whopping 2,900! This is almost a six fold difference in performance within this narrow price range. So it really pays to do your homework before you buy. If you don't, you risk buying a machine one-fifth as fast as you could have had for the same money.

But how do you do your homework? Not even the geekiest of us is willing to spend the scores of hours it would take to find detailed test results for all the possible models of PCs we might consider buying. But one can get a fair idea of a PC's performance potential just by looking at benchmark results for the CPU (central processing unit). This is easy stuff.

The quickest way is to look at URL http://www.cpubenchmark.net/cpu_list.php . To do your homework, just read the advertisement for a PC, consult this web page, and write down the benchmark value for the CPU listed in the ad. Do this for all the PC advertisements in your price range, and you'll quickly and easily get a good idea about which PCs might be the top performers in your price range.

This is not a definitive answer, of course. The CPUs processing speed is just one part of the PCs overall speed. The size of the L2 cache, the quantity of RAM, the type of RAM (DDR2 or DDR3), and the motherboard configuration all play into how fast a particular model of PC will perform. But if you don't overpush the CPU Benchmark numbers, you can get a pretty good idea. We don't think you can really tell whether one machine will be faster than another if their CPU benchmarks are within 30 percent of each other. In this case, the PC with the lower CPU benchmark might be paired with other components that are superior, and might actually outperform the PC with the higher CPU benchmark. But when one CPU is 60 percent faster, you can be pretty sure the PC it is in will be faster too. And when you see a CPU benchmark that is double, triple, or even five or six times faster, then you surely know that the PC it is in is also faster. And you will see this range of variance in CPU benchmarks for PCs that sell for the same price.