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» MEDIA (17) Figure 1 - Pentium D Image Figure 2 - The Pentium D Family Figure 3 - 3DMark 2006 CPU Benchmark Figure 4 - SiSoft Sandra Multimedia Integer Benchmark Figure 5 - MAME Benchmark Figure 6 - Unreal Tournament Benchmark Figure 7 - TMPGEnc MPEG-2 Encoding Benchmark Figure 8 - Ulead MovieFactory 5 Benchmark Figure 9 - BIOS Screenshot Figure 10 - 3DMark 2006 Overclocking Benchmark Figure 11 - SiSoft Sandra Overclocking Benchmark Figure 12 - MAME Overclocking Benchmark Figure 13 - Unreal Tournament 2004 Overclocking Benchmark Figure 14 - TMPGEnc Overclocking Benchmark Figure 15 - Ulead MovieFactory 5 Overclocking Benchmark Figure 16 - Overclocking Temperatures Figure 17 - Final Verdict

Introduction

If you don’t currently have a dual core processor, there’s a major corporation that would like to know why.

In the middle of 2005, Intel announced its new Pentium D series, which was their first foray into the world of mainstream desktop dual core processors after tentatively pursuing the high-end market with the Pentium 4 Extreme Edition. It soon became apparent that Intel may have been the victim of its own marketing during its “Hyper-Threading” campaign of 2002-2004, as it shipped only about 500,000 of the processors during the first 8 months following the announcement of the new processor line. Consumers were confused, asking “Doesn’t my processor already do multithreading?”. Equally, the new processors carried a price point significantly above existing Hyper-Threading CPUs, with the entry-level 820 (2.8GHz) processor coming in at $250, versus a comparable Pentium 4 520 at $170, a premium of 32%. Intel needed to do something to spur the move to dual-core, but it needed to do so without undermining the price point of existing CPUs on retail shelves.

Enter the Pentium D 805 processor.

“The purpose of the 805 is to drive dual-core technology into mainstream-value pricing, which it will do” European website The Inquirer quoted Intel’s Todd Garrigues, North America channel marketing manager for boxed products as stating. Indeed, the chip was a departure from the existing Pentium D line, with the FSB of the processor coming in at a sluggish 533MHz, as opposed to the 800MHz speed which had been commonplace for several years.

(See Figure 1 – Photo of Pentium D)

Pentium D 805 Specifications

Clock Speed: 2.66GHz
Core: Smithfield
FSB: 533MHz
Voltage: 1.25-1.4V
L1 Cache: 16K+12 Kuops
L2 Cache: 2x1MB
Process: 90nm
Socket: LGA775

(See Figure 2 – Processor Family Chart)

On paper, the 805 clearly was inferior to its Pentium D 8xx siblings. At such a low price point, however ($130 USD in 2006), value PC makers began to enthusiastically shove the chip into their existing systems, allowing them to tout their dual-core capability without raising prices. Enthusiasts, however, smelled the potential of the 805 to do more, given the very low FSB and not-so-low 20x multiplier. Was this inexpensive little processor a diamond in the rough?

Test setup:

Both Pentium D 805 and Pentium 4 520 processors were used on the test bed system. Tests include both single-thread and multi-thread applications, with the intent to show what performance improvement (if any) was to be gained with the addition of a second core.

ASRock ConRoeXFire-eSATA2 (Intel 945P chipset)
2x512MB Elixr DDR2 memory (4-4-4-12 timing)
ATI X600 PCIe graphics adapter
Western Digital 250gb HD
Pioneer DVR-710 DVD Writer
Windows XP Professional Service Pack 2

Synthetic Benchmark 1 – 3Dmark 2006

Futuremark’s 3dMark06 is a suite of benchmarks, designed to approximate what a gaming system might be subjected to. The CPU tests in particular do AI and physics simulations (using, among others, Ageia’s PhysX SDK) in an immersive volcanic scene.

(See Figure 3 – 3DMark benchmark)

The Pentium D 805 shows a strong advantage in this test over the Pentium 4 processor due to the addition of the second core. The engine used for the CPU test in 3DMark is heavily multi-threaded, which is fairly consistent across all modern synthetic benchmarking applications. The 805’s advantage was nearly 75%, despite the higher clock speed and FSB of the Pentium 4 processor.

Synthetic Benchmark 2 – Sandra Lite Multimedia Integer v11.26

The venerable Sandra, from SiSoftware, is one of the best-known synthetic benchmark applications for Windows. Its approach differs from that of 3DMark in that it focuses less on gaming performance, and more on raw performance of core system components.

(See Figure 4 – SiSoft Benchmark)

The fact that Sandra’s Multimedia Integer benchmark is multi-threaded is obvious – the Pentium D comes out ahead in this benchmark as well, scoring roughly 34 percent better than the Pentium 4. SiSoft confirms in their FAQ page that they have seen substantially less improvement in their arithmetic tests in transitioning from a single core NetBurst-architecture processor to a dual core NetBurst – this has to do with the design of the processor itself. A 34% improvement remains a substantial boost, however.

Gaming Benchmark 1 – Performance using MAME

In order to ensure that the benchmarks accurately depicted the relative performance of the CPU, it was crucial to work around any bottlenecks that the ATI X600 video card in the test system would introduce. As such, it was important to choose games which were not overly taxing on the video card, while simultaneously pushing the CPU to its limits.

The Multiple Arcade Machine Emulator, or MAME, was chosen for the first gaming benchmark, as it emulates all functions of an arcade system (CPU, graphics, sound) using the processor only. It is, however, only able to make very limited use of multiple threads due to the delicate timing involved in emulation, so we see only a slight variation in performance when using either a single or dual core system.

MAME was run from the command line, using Tekken 3’s ROM set as input. Frame count was limited to the first 5000 frames found in the game, which cycled through several iterations of the game attract screen.

(See Figure 5 – MAME Benchmark)

Even with the limited use of multi-threading in MAME, a performance boost of nearly 20 percent was observed between the two processors. This was in spite of the slightly higher clock speed and 800MHz front side bus of the 520. By itself, the multi-threaded code optimizations were not reason enough for the boost – rather, a significant amount of the performance increase was due to the availability of an additional processor core to handle functions in MAME, instead of being used for operating system overhead. This is a very important thing to remember – even in applications not designed with multiple threads in mind, a significant improvement in performance can indeed be had by simply offloading the unrelated processing duties to the other core in the system.

Gaming Benchmark 2 – Unreal Tournament 2004, 640x480 Colossus Map

Keeping in mind the aforementioned concerns about the graphics card adversely affecting gaming benchmarks, Unreal Tournament 2004 was chosen due to its relatively low graphics requirements and CPU-intensive gameplay. To further remove the graphics card from the performance equation, the game was run at 640x480 with the “high performance” setting in UMark.

(See Figure 6 – Unreal Tournament 2004 Benchmark)

The aging Unreal Tournament 2004 was written before the proliferation of multi-core systems, and the benchmarks reflect that reality. Interestingly, with no apparent optimizations to take advantage of the Pentium D 805’s architecture, the Pentium 4 520 actually comes out about 3 percent ahead due to its higher clock speed. During this game, the second processor sat largely idle, and the Pentium D’s potential was left untapped.

Encoding Benchmark 1 – TMPGEnc Video Encoding (Convert AVI to MPEG-2, 720x480 DVD template)

TMPGEnc was used to convert an 18 minute AVI video to MPEG-2, using the DVD template found within the project wizard. This software takes full advantage of the second core, as is evidenced by the difference in performance between the Pentium D and the Pentium 4 processor.

(See Figure 7 – TMPGEnc MPEG-2 Benchmark)

Many encoding applications are now written to be fully multi-threaded, and really give systems with multiple cores the opportunity to shine. Here, we see the Pentium D 805 beating the Pentium 4 520 by nearly 50 percent.

Encoding Benchmark 2 – Ulead DVD MovieFactory 5

Ulead has been a name in video editing for over a decade. Ulead MovieFactory 5 is an application geared toward the entry-level DVD author, with simple menus and limited control over burn settings. For this test, the same 18 minute AVI file was converted to MPEG-2 format, and written to an ISO file on the C drive. The DVD menu was included for the ISO file, but no text was entered into the menu.

(See Figure 8 – Ulead MovieFactory Benchmark)

This is an example of an application which – while multi-threaded to an extent – did not take full advantage of the second core. The Pentium D 805 does eke out a victory over the Pentium 4 520, but the 20% margin is noticeably smaller than it was in the TMPGEnc benchmark. Re-running the benchmark while watching the task manager confirmed that both processor cores were indeed seeing some activity, but while one core fluctuated between 70 and 85 percent, the other core was only lightly used in the 15-30 percent rage. This illustrates a clear lesson: The architecture of software varies greatly, and performance will vary as a result.

Overclocking

As is the case with all current Intel chips, the Pentium D 805 has a multiplier lock in place. This means that we have only the FSB to play with to increase the clock speed of the processor.

(See Figure 9 – Photo of BIOS Settings)

The image shows the nature of the options that the ASRock motherboard has for overclocking. Host frequency is increased in 1MHz increments, which results in a 4MHz increase in FSB speed. The FSB speed is then multiplied by 20 (the multiplier of the Pentium D 805), which gives us our CPU clock speed.

Reports abound of the Pentium D 805 overclocking to rates beyond 4GHz. The success of the test bed system was significantly less, however, reaching a maximum POST of only 3136MHz using stock air cooling. The increase of 470MHz translated into a gain of 15% in performance benchmarks:

(See Figures 10 through 15 – Previous tests with overclocked CPUs included)

As expected, the 805 processor performance increases proportionately to the clock speed. For anyone currently using a single-core Pentium 4 processor, the improvement is very noticeable, even under a relatively mild overclock.

Processor Heat During Overclocking

The processor temperature was measured using SpeedFan 4.32 Final, by Alfredo Milani Comparetti. The temperature was measured both with the processor at idle for 10 minutes, as well as running under full load in a TMPGEnc MPEG-2 encoding process for 20 minutes.

(See Figure 16 – CPU Temperature Readings during Overclock)

Unfortunately, the motherboard of the test bed system (ASRock ConRoeXfire-eSATA2) has no VCore options whatsoever, and a hardware modification of the board was ruled out for this evaluation. Due to the fact that the BIOS reported an active VCore of just under 1.25V, and given that the heat of the processor only reached a maximum of 65 degrees Celsius under load at the 3136MHZ speed, it is highly probable that the processor itself was under-volting (rather than overheating), and could have gone higher with a different motherboard configuration.

Check out FiringSquad’s CPU Overclock Database for further evidence of the flexibility and potential of this processor. As always, however, your mileage may vary.

Ballistics Report

The Good

Single Core Price, Dual Core Performance: The Pentium D 805 was a bargain when it came out, and remains a bargain today. For anyone who wants to upgrade from their existing single-core system, this is an inexpensive way to move to dual core without replacing their motherboard. As always, check the CPU support table from the manufacturer first.

Overclock-Friendly: This CPU, when paired with a motherboard with the correct options, overclocks very well. Even the unimpressive ASRock motherboard used in this review was able to achieve a speed increase of roughly 15% using stock air cooling with no VCore tweaks at all.

Increased Use of Multiple Cores: While earlier games and applications were generally written without multi-core systems in mind, performance-hungry software packages are increasingly turning their attention to the second processor. The Pentium D 805 is therefore poised to take advantage of evolving software architectures in a way that a single core processor simply cannot.

The Bad

Plodding Bus Speed: This CPU is the only model in the Pentium D line to use a 533MHz bus. This is hardly impressive, considering Intel has been using an 800MHz bus speed in its processor line since 2003.

Heat: Due to its Prescott lineage and 90nm manufacturing process, this processor puts out significant amounts of heat. The situation is even worse when overclocking, requiring higher-end solutions to reach the frequency potential of the chip.

Legacy Architecture: For all the good that is found in this processor, it is saddled with the legacy of the NetBurst architecture, which has been around since 2000. The result is that, even if one is successful in overclocking the processor to extreme levels, it will still be outperformed on a clock-by-clock basis by any Core architecture CPUs.

Verdict

(See Figure 17 – Final Verdict)

For historical reasons alone, one must recognize the importance of the Pentium D 805. Many analysts have suggested that Intel used the middle of 2006 to launch a price war against AMD, and this processor was the spearhead of the effort. It gave the value price point an introduction into dual core processing, and the rest of us were able to pick up a capable, easily overclockable processor on the cheap.

Intel has informed its distributors that orders for the 805 processor have now ended, though shipments will continue through the end of the first quarter of 2008 for the OEM version of the chip. Paired with an overclock-friendly motherboard and solid cooling, these processors are a steal at $65 (Newegg.com), even in the face of newer technology in the Core 2 Duo series. If you have an older Intel 945 or nForce4-based motherboard and don’t fear experimenting with overclocking, this chip is one of the best options available to extend the life of your legacy system for another year. Even at stock speeds, however, the Pentium D 805 processor represents an important step forward for anyone still using a single core processor.

If you’re thinking of upgrading an existing system to dual core, consider picking it up today – before it takes its place alongside the Celeron 300A as one of the most desired discontinued overclocking processors in Intel’s history.