The Dell T5400 model is slightly faster on graphics, but has a slower and smaller disk (80GB). The HP xw6600 had a faster, more capacious hard drive (250GB), but is about 7 percent slower on the graphics. The Dell system has slightly better expandability as regards the PCI Express slots. It has two more slots, both of which are PCI-X 64-bit. It also has a more capable power supply. For these reasons, I could see giving a slight edge to the Dell Precision T5400, but considering that their prices are nearly identical and pricing varies widely from week to week due to sales promotions, I suggest that if these models appeal to you, you should buy from your preferred vendor or base your decision on price at the moment of purchase.

When two models are so close, it is customary for reviewers to suggest that both models should be evaluated before a decision is made. While that advice is certainly applicable, it's not my first recommendation. Rather, I think you should examine the comparative benefits of the other two machines: the value-oriented HP xw4600 and the high-end Dell Precision T7400. In both cases, I think you get more value for the dollar.

The sweet low end
The HP xw4600 is a very capable workstation that costs less than half of the two midrange systems, and it delivers much of their wallop. As reviewed, it has a single Intel Core 2 Quad quad-core processor running at 2.4GHz, an Nvidia Quadro FX 1700 graphics card with 512MB of video memory, and 4GB of system memory. It also has the same form factor and whisper-quiet operation of its larger xw6600 sibling.

However, look at the performance. Its SPEC ViewPerf rating of 47 puts it only slightly behind the two midrange systems. The CPU results (see benchmark results table) are approximately half of theirs, but it also has half as many cores. As a result, core for core, this system is close to the performance of the midranges. The question that becomes critical is whether you need eight cores. Surprisingly, even for workstation applications, the answer is often no. Both Dell and HP stated that the bulk of their current workstation sales are for quad-core, not eight-core systems. And unless your software will truly use all eight cores and needs to do so frequently, the quad-core system will frequently be just the right solution. If so, the xw4600 is where you should start looking. Consider this: If you were to pull one of the processors out of the midrange systems, their performance profiles would look a lot like the xw4600, but their prices would be much higher.

The xw4600 also has some unique, ingratiating aspects. Its power consumption is very moderate. It runs at 88W when at 0 percent. And when it's going flat out at 100 percent, its wattage is less than any of the other systems at rest. That's saying something. Essentially, the heat generated from the xw4600 is never going to be an issue.