I used the Sandra XII benchmark suite from SiSoftware to measure component performance. This suite is probably the best and most comprehensive suite available for x86 desktops and servers. A free personal version is available from SiSoftware's Web site. Graphics were tested using the highly regarded and freely available ViewPerf 10.0 benchmark suite from SPEC (Standard Performance Evaluation Corporation). ViewPerf works as a Windows-only series of tests that assesses a system's video capabilities. Its final mark (the average of five benchmark results) is influenced by both the graphics card and the system processor. I ran the Quad version of ViewPerf 10.0 on all the workstations.

And for the first time, InfoWorld is benchmarking workstation power consumption. To do this, I used the P3 Kill-A-Watt Electricity Usage Meter, which I highly recommend. It's inexpensive, it's accurate, and it gives all sorts of electrical data. I measured power consumption at rest (processor at 0 percent operation, with the system not hibernating) and at peak (100 percent operation for all processor cores). To obtain a single power rating for a machine, it's useful to employ the same power-consumption measure published in the recently released EnergyStar 4.0 specification. Its formula is:

                    Rating (in watts) = 0.35 (Pmax + (HDD x 5))

Pmax is power consumption when the system is running at 100 percent, and HDD represents the number of hard drives on the system. This mark is given in the benchmark results table for each workstation. Between it and the other two figures plus the handy power meter, you can see how your current systems compare with those reviewed here. I suspect you'll find the reviewed workstations are surprisingly efficient. All four rely on 80+ power supplies (meaning more than 80 percent of the incoming power is transformed into power for the workstation), and both HP machines have been given EPEAT Gold certification for meeting a series of environmental criteria.

The middling midrange
Both midrange workstations, the Dell Precision T5400 and the HP xw6600, are impressive in several respects. They are small — smaller even than standard desktop PCs. They are also almost completely silent. Save for the Dell startup routine in which it races its fans, there is no difficulty hearing a clock tick over the faint hum of these systems. Their heat dissipation is also remarkably good, considering their 0 percent load consumption is a healthy 189 watts. Most of the time, it is barely noticeable, even in a small office. At full tilt, however, the heat they throw off becomes quickly apparent.

We asked Dell and HP to use the same models of quad-processors (Intel Xeon E5430 chips running at 2.66GHz) and to load the systems with Microsoft Windows XP Professional SP2. We then asked them to deck out the workstations with any additional hardware they wanted that would still put the price in the roughly $5,000 range. As can be seen from the features table, both companies made essentially the same choices: Nvidia Quadro FX 4600 graphics, 4GB of system RAM, and motherboards using the same chip set. Because of this, their benchmark results are approximately even.