Lab test: Four Dell and HP workstations
- 20 May, 2008 12:33
There was a time when workstations occupied a highly competitive niche in the hardware market. In those days, some 10 years ago, companies such as Sun Microsystems, SGI, IBM, HP, and Dell competed fiercely to deliver the top desktop systems characterized by powerful graphics and processing engines. An added element to this competition was the vendors' reliance on vastly different processor architectures to deliver the knockout performance. A decade later, the market segment is significantly different.
Today, the RISC processors that characterized the Sun, SGI, IBM, and HP machines are mostly memories, and all leading workstations are built on x86 processors. The number of vendors has also shrunk dramatically. SGI abandoned workstations, IBM's workstation division has morphed into Lenovo, and Sun -- a once-dominant player -- occupies a minor niche. On the one hand, this evolution has led to a market that is homogeneous in its product delivery and devoid of the intense competition of days of yore. On the other, workstations today deliver unimaginably more power than a decade ago at undreamed of prices.
To get a good cross-section of the market, we contacted the four principal vendors of x86 workstations, Dell, HP, Lenovo, and Sun, and requested dual-processor, quad-core machines as a midrange baseline. Only Dell and HP could provide such systems. Sun was in a prolonged holding pattern waiting for AMD to ship quad-core Opterons (Barcelona). And Lenovo, which is just starting up its workstation line of business, could not respond with the configuration we wanted within our time frame. We expect to review machines from both vendors in the next few months.
Meanwhile, this lab review focuses on major players HP and Dell, who together own the lion's share of the market. We asked them each for a midrange system costing US$5,000 retail, and we required they use identical processors, the same amount of RAM, and the same releases of Windows XP so that we could compare what other magic they could add to this base and still stay at US$5,000. As we'll see shortly, the magic looked a lot alike. We also examined a value-oriented system from HP and a very high-end workstation from Dell. Curiously, the high and low ends appear to represent the best values, while the midrange serves as a refuge for those who don't want to spend for the high-end Dell, and whose needs are not met by the entry-level HP.
The benchmarks I used in this evaluation represent a departure from the metrics traditionally used. I decided to rely solely on high-quality benchmarks available at no cost to readers. This approach gives excellent quantitative insight, while allowing you to reproduce our tests on your systems.
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, we are 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 per cent operation, with the system not hibernating) and at peak (100 per cent 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 per cent, 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 per cent 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 per cent 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 US$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.
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 per cent 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 per cent. And when it's going flat out at 100 per cent, 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.
The workstation also has unique expandability, including eight drive bays and 10 USB ports -- more than any other system reviewed here. One of those ports is internal, a comparatively new development. Internal USB ports are located inside the systems for use by dongles. By putting the dongle ports within the workstation, the problem of software keys being misappropriated is greatly reduced. The only expandability not included on the xw4600 is a second processor socket. You get just one quad-core chip on this machine. However, the US$2,056 price tag includes four-hour onsite service, which is better than any of the service plans for the other systems.
In my view, this is where you should begin the search for a workstation. Unless you have very heavy processing needs and the software to make use of eight cores, this might also be the place where search will end as well. (Most ISVs should be able to tell you whether their software can take advantage of eight cores. Even with this vendor information, you should run a trial on an eight-core system to validate the claim yourself.)
The heavyweight champ
Dell's Precision T7400 workstation is everything the HP xw4600 is not: It's big, hot, and noisy. But it delivers truly remarkable processing power. It is driven by two Intel Xeon 5482 chips, running at 3.2GHz -- the current top of the line for x86 processors. These silicon wonders are hooked up to the Nvidia Quadro FX 4600 graphics card, and this combination hits 94.45 on the SPEC ViewPerf benchmark, which is nearly double the graphics performance of the midrange twins (see benchmark results table).
Dell has added another performance bonus: a pair of hard drives wired together to make a single 146GB Serial Attached SCSI disk (SAS) that runs at 15,000 rpm, but benchmarks at 20,000 rpm due to Dell's I/O technology. This apparent rotational speed plus the use of the SAS drive means that the T7400's disk reaches an extraordinary 189MBps data transfer rate with a lightning-fast random access time of 6ms.
Except for adding more RAM (and this system goes up to 64GB with risers to double up the eight DIMM slots currently available), this workstation represents the top of the line or very close to it in the three most important performance areas: processors, graphics, and I/O. In sum, it's the pinnacle of desktop power. And -- this is the remarkable part -- it's available for less than US$8,000. At this price -- US$3,000 more than the midrange machines -- it becomes a suitable choice for users who are not convinced the midrange workstations will have enough power down the road. Large-scale simulations (both in research and industry) and complex rendering of large data sets might be possible applications.
Money and power
Personally, I think many, if not most, workstation use cases can be satisfied with the entry-level xw4600 from HP. This conviction grows if your software cannot take full advantage of eight cores and will do so regularly. Unfortunately, this recommendation is not reflected in the system scores presented at the beginning of this article. This discrepancy is due to the large weighting given to performance, and when this system competes with high-end workstations, it will unavoidably suffer.
Users whose requirements don't fit with the xw4600 probably need the best workstation the market has to offer, barring ridiculous extremes. In such a case, the Dell Precision T7400 definitely fits the bill. The midrange machines -- and, again, either system will do -- fill the gap for those who need somewhat more than the xw4600 and don't want to put out US$8,000 for the high end or don't wish to put up with the noise, heat, and size of the Dell T7400. In essence, the midrange twins are for folks who need a little from either the top or the value end of the workstation spectrum.