Next-Generation PCs

More Memory

Another big factor affecting performance is RAM. Vendors still seem to think 1GB of RAM is the sweet spot, as four of our test systems came with 1GB of either DDR (for AMD systems) or DDR2 (for Intel systems) memory. But our Test Center believes that the Xi MTower's 2GB of RAM probably made a substantial contribution to that machine's achieving the best WorldBench 5 score that we've seen.

For anyone moving massive amounts of data--while editing digital video, for example--there is no such thing as too much RAM. All the systems we tested except the Sony VAIO VGC-RA842G can support a whopping 8GB of RAM. But you'll need to be running a 64-bit operating system such as Windows XP Professional 64 Edition if you want to use more than 4GB.

Speedier, Safer Storage

The biggest news in storage doesn't concern just speed; it also relates to the safety of your data, or the lack thereof.

RAID, the Redundant Array of Independent Disks, was once an expensive technology exclusive to servers and high-end workstations. It speeds up data transfer and protects stored data by linking together multiple hard drives in a single PC. RAID comes in seven official levels, RAID 0 through RAID 6, plus a couple of extensions (RAID 0+1 and RAID 10) and proprietary implementations (RAID 7 and RAID S), with each level offering different trade-offs between performance and fault tolerance. (Fault tolerance is a system's ability to keep running if part of it fails. Also, the numbers used in RAID levels do not indicate that a higher number is better.) Every system here, except the Power Mac G5, supports at least RAID 0 and RAID 1 in hardware.

Five of the systems we examined came with two hard drives configured as a RAID 0 array. RAID 0 spreads, or stripes, data across two or more drives so files can move on and off the drives faster--two hands are better than one, so to speak. For anyone who moves lots of data, such as engineers or graphics professionals, RAID 0 can speed up many tasks substantially. But for the average user, RAID 0 has one serious drawback: It provides no fault tolerance in case one of the drives crashes.