In December 2002's print issue of PC World (on page 94) we talked about Intel's new 3.06GHz Pentium 4 CPU and three new chipsets -- the Intel 845PE, the enhanced version of the 850E, and the 845GE -- which will cater for it and its new feature, Hyper-Threading technology. We were unable to bring you benchmarks of the CPU and this technology in the print issue because the news-stand date was earlier than the technology's embargo date; we have now passed the embargo date, however, so we are using the Web site to provide some relevant benchmarks that illustrate how Hyper-Threading can boost the performance of a desktop PC.
Operating environmentIt is important to note that Hyper-Threading technology is a multi-threading feature built into the Pentium 4 that, in essence, makes the operating system think two processors are installed, when in fact it's just one physical processor that is logically designed to work as two. Multi-threading is a method some programs use to execute two tasks simultaneously. It works on the premise that the CPU is never used to its full potential in any given cycle, therefore the remaining processing power can be allocated to another thread during that same timeframe (cycle). As such, to benefit from Hyper-Threading technology you will require an operating system that supports multiple CPUs, so Windows 98, Windows 98 SE and Windows Me are all out of the question. Although Intel does not recommend Windows 2000 or Windows NT4.0 as being optimised for Hyper-Threading technology, Windows XP Home and Professional will have no problems supporting Hyper-Threading. Some of the latest Linux distributions may also support the technology.
Chipset supportAs previously mentioned, the latest chipsets for the Pentium 4 are the 845PE, the 845GE and the enhanced version of the 850E chipset. These all accommodate higher memory bandwidth and, of course, support for Hyper-Threading technology. Hyper-Threading can be either enabled or disabled through the BIOS of the motherboard (see FIGURE 1a) and the operating system must be installed after the CPU is installed in order for Windows to recognise the CPU as a multi-processor model. Once you open the Device Manager, the description under Computer should read ACPI Multiprocessor PC (see FIGURE 2). It is important to note that if your CPU does not support Hyper-Threading, yet your motherboard chipset and BIOS do, the Hyper-Threading option may not be available in the BIOS (see FIGURE 1b). To find out if your Pentium 4 motherboard supports Hyper-Threading, visit your vendor's Web site or go to www.intel.com/design/chipsets/ht.
|FIGURE 1a: Hyper-Threading can be enabled or disabled through the BIOS.||FIGURE 1b: The Hyper-Threading option will be missing if your CPU does not support Hyper-Threading.|
FIGURE 2: Windows XP Home Device Manager shows a Multiprocessor PC.
How we testedWe tested the CPU with the industry standard benchmarks we regularly use to test the PCs in the Best Buys, which are Bapco SYSMark 2001 and MadOnion 3DMark 2001 SE (build 330). We also used the Quake 3 timedemo 1 benchmark at various resolutions, and we performed various multitasking tests, which are discussed below. Our test platform was an Intel D850EMV2 motherboard with 512MB of PC1066 RDRAM, an Albatron 128MB GeForce4 Ti 4600 graphics adapter, and a 7200rpm 120GB Western Digital Caviar hard drive. These components were installed in an Antec case, which featured a power supply of 400W. A fresh copy of Windows XP Home was installed and we tested the CPU with Hyper-Threading both enabled and disabled through the BIOS in order to gauge the effect of the technology in an everyday computing environment.
SYSMark 2001The results we received for SYSMark 2001 seem to suggest that Hyper-Threading technology holds little promise and, in fact, provides a performance hit for office applications. As you can see from the performance table, when the CPU had Hyper-Threading enabled it produced a score around 4 per cent lower in this benchmark than the run that had Hyper-Threading disabled in the BIOS. Specifically, the run with Hyper-Threading enabled showed around an 8 per cent decrease in performance in office productivity tests when compared to the run with Hyper-Threading disabled, but the Internet Content Creation performance was identical under both scenarios. The 3.06GHz CPU with Hyper-Threading enabled proved to be 4 per cent faster than the 2.8GHz CPU and 8 per cent quicker when Hyper-Threading was disabled.
3DMark 2001 SE and Quake 3This benchmark was used to evaluate the CPU's graphics performance at a resolution of 1024x768 with 32-bit colour depth and at the higher setting of 1600x1200 with 32-bit colour depth. As you can see from the results, this benchmark showed marginal improvements when Hyper-Threading technology was enabled as opposed to when it was disabled, with the enabled run almost cracking the 13,000-point barrier. Turning our attention to the Quake 3 Timedemo 1 results, we can see that the CPU was able to pump out more frames per second at all settings when Hyper-Threading was enabled. Resolutions higher than 1024x768 will rely more heavily on the graphics card and, as you can see, at the setting of 1600x1200 with 32-bit colour depth, an identical score was achieved in all tests.
|Pentium 4 3.06GHz||Pentium 4 2.8GHz|
|Hyper-Threading Enabled||Hyper-Threading Disabled|
|Internet Content Creation||318||318||297|
|3DMark 2001 SE (build 330)|
|1024x768 with 32-bit colour depth||12997||12878||12589|
|1600x1200 with 32-bit colour depth||7922||7908||7820|
|640x480 with 16-bit colour depth||317||306||302|
|640x480 with 32-bit colour depth||316||306||302|
|1024x768 with 16-bit colour depth||292||286||282|
|1024x768 with 32-bit colour depth||283||277||274|
|1600x1200 with 32-bit colour depth||154||154||154|
Multi-taskingWhere Hyper-Threading technology really makes its mark on an everyday desktop is multi-tasking. One simple test we conducted to get a feel for the multi-tasking capabilities of Hyper-Threading involved converting music files from MP3 to WAV format in the background of a Quake 3 gaming session. In these tests we used MusicMatch Jukebox to first encode a 77-minute audio CD to MP3, using a bitrate of 320Kbps for the output files, and then we used Winamp to decode these same files from MP3 to WAV format. Both these tasks took the same time to complete, regardless of whether Hyper-Threading was enabled. Measuring the CPU usage of the machine while decoding the files, it is worth noting that with Hyper-Threading disabled (FIGURE 3a), the MP3 to WAVE conversion test used close to 100 per cent of the CPU during this task. With Hyper-Threading enabled (FIGURE 3b), total utilisation was closer to 50 per cent, which is one of the reasons we were able to play a game effortlessly while performing this task.
|FIGURE 3a: CPU utilisation reaches levels close to 100 per cent.||FIGURE 3b: CPU utilisation is much improved when Hyper-Threading is enabled, allowing other tasks, such as game playing, to be accomplished with relative ease.|
Quake 3 was run at a resolution of 1600x1200 with 32-bit colour depth to see if we could effectively play a game while Winamp was encoding. With Hyper-Threading enabled in the BIOS, Quake 3 reached an aggressive 130fps in numerous test runs while the encoding was going on in the background. The encoding process did take slightly longer, but did not slow down to a crawl. In other words, the CPU capably handled both tasks at the same time and was able to assign resources to each task in such a way that a performance hit was not noticeable. With Hyper-Threading disabled in the BIOS, Quake 3 proved to be unplayable until the decoding process was completed. That is, the CPU had to finish the decoding process before it could concentrate on the game. At this stage it is important to note that multi-tasking performance will be boosted only if the applications you are running concurrently are not of the same nature. For example, you won't be able to play two games at once or run two instances of encoding, as they will both be vying for the same resources.