Best PC Upgrades

CPU

Photograph: Marc Simon

Intel's new Core 2 Duo chips shook up the CPU market this July. Our first tests of Core 2 Duo systems yielded the highest WorldBench 5 benchmark scores we've ever seen, easily outshining the best marks from systems running on AMD's available dual-core offerings. If you're shopping for a new PC, a dual-core chip is a good idea, whether it's one of Intel's new screamers or an AMD Athlon 64 X2 or FX. But Core 2 Duo is the chip that looks like a breakthrough product.

In our tests of similarly built reference PCs, a system configured with a 2.93-GHz Intel Core 2 Extreme X6800 processor turned in a blazing WorldBench 5 score of 160. An AMD Socket AM2 FX-62 PC equipped with a 2.8-GHz Athlon 64 FX-62 lagged a good distance behind with a score of 137. For further test results on these and other comparable machines, see "Intel's New Core 2 Duo Processors Run Blazingly Fast in PC World Tests."

The bad news is that you can't just pop a Core 2 Duo chip into your existing motherboard. The chips use the same socket 775 as existing Pentium 4 and Pentium D processors, but they require additional hardware support in the form of a new chip set and a specially designed motherboard. Meanwhile, AMD's latest dual-core chips use a new socket called AM2, which means that you can't move up to those chips without either swapping out the motherboard or buying a new PC.

So what can you get that works with your current motherboard? Well, that depends in part on your CPU socket. Older Pentium systems use socket 478 processors. Recent Athlon systems use either socket 939 or socket 754. Check your system or motherboard manufacturer's documentation or Web site to find out which socket type you have, or download one of the time-saving system utilities we look at on page 108.

Once you know your socket type, you can check to see what compatible options are out there. Good places for shopping include Newegg.com, PCMall.com, and shopping metasites like DealTime.com and Shopzilla.com. Just remember that the older the chip is, the harder it will be for you to find a suitable upgrade. Plenty of upgrade processors are available for recent systems using socket 754, 775, or 939.

We tested many different upgrades to see how much life we could wring out of a two-year-old test PC; the CPU swap offered the biggest gains for any single upgrade in our WorldBench 5 tests. If you're thinking about swapping out your CPU, look for an improvement of 1 GHz in clock speed to justify the cost. And whenever possible, buy a retail package kit--not just the CPU--since you'll get a much longer warranty as well as the appropriate heat sink and fan.

Saving an Old System

Our older custom-built PC had 512MB of system RAM, a Gigabyte motherboard, and a 2.6-GHz Pentium 4 CPU. The upgrade window on socket 478 Pentium systems is closing rapidly, but we found a 3.2-GHz Pentium Extreme Edition chip that we could plug in.

The $300 chip we used isn't cost-effective if your CPU already runs at 2.8 GHz or better (though you can save about $100 by getting a slightly lower-power, non-Extreme Edition 3.2-GHz Pentium 4). But even the 600-MHz increase in our test system provided nice results. The upgraded PC bumped up a healthy 17 percent on WorldBench 5 from a score of 75 to 88--comparable to today's all-purpose laptops.

To figure out whether your CPU could use a power boost, hit <Ctrl>-<Alt>-<Delete> in Windows to call up Windows Task Manager (or see "Gauge How Hard Your System Is Working," for a more advanced performance tool). The green box in the system tray provides running commentary on how hard your processor is chugging away (alternatively, you can look under the Performance tab in the Task Manager window for a more precise display of data). Run through your normal tasks, and keep an eye on the tray icon, especially when your system feels slow. If the processor is regularly running full-bore for extended periods, you'd likely benefit from a CPU upgrade. Note that some tasks, like running a full virus scan, will push just about any processor. One tip: If you want to keep the Task Manager from cluttering your taskbar, choose OptionsHide when minimized. You can bring it back by double-clicking the system tray icon.