The 1.7 GHz Pentium 4

One of the biggest advantages of the P4 architecture is that it is highly scalable and the clock frequency can be increased rapidly. That is one reason by the time we finished reviewing this processor, the 1.8 GHz version was out, and why a 2 GHz processor will be out by the time you read this.

Technology overview

Let’s first take a look at the Hyper-pipelined technology in the P4’s NetBurst micro-architecture. A pipeline is a set of stages through which a microprocessor instruction passes. Each stage can execute an instruction simultaneously with another. This way the processor starts executing a second instruction even before the first one is completed. So ideally, more stages in the pipeline means that more instructions can be executed simultaneously. The P4 has a 20-stage pipeline, which is just double of the previous Intel architecture.

Another major feature of the P4 is a quad-pumped 100 MHz FSB, which means that the processor effectively has a 400 MHz bus. Also, it has 144 new instructions called SSE2 (Streaming SIMD Extensions 2), which can speed up certain types of calculations by replacing several instructions with

one.

Performance

We tested the processor on an original Intel 850 chipset motherboard, with a GeForce 2 Ultra handling the graphics. The remaining configuration consisted of 128 MB RDRAM and a 7,200 rpm IBM hard drive. We compared it to the latest AMD Athlon 1.4 GHz using the same RAM, graphics card, and hard drive.

First we ran Business and Content Creation Winstone 2001 benchmarks for testing productivity and graphics application performance. The Athlon scored 51 leaving the P4 behind at 45.6. Content Creation Winstone gave the same 10 percent difference with the Athlon scoring 49.2, and the P4 scoring a 44.1.

However, the story was in the P4’s favor in gaming. In 3D Winbench 2000, the P4 scored 164 fps compared to Athlon’s 155 fps, a difference of 5 percent. Gaming performance in Quake III Arena gave a similar picture. Quake III, for some reason unknown to even its primary programmer John Carmack, runs exceptionally well on the P4. We got a whopping 227 fps at 640x480 resolution with 16-bit color depth, as against a 195 fps scored by the Athlon. At a very high resolution of 1280x1024x32 however, the Athlon scored 84 fps, compared to a lower 72 fps done by the P4. At low resolutions, the processor governs the frame rates to a large degree, whereas the system becomes clogged for bandwidth at high resolutions and usually becomes a function of the video card.

Since the 1.7 GHz is the latest Intel processor, its cost will be significantly higher than the 1.5 GHz (last price we got was Rs 24,000 for the 1.4 GHz processor, motherboard, and 128 MB RDRAM). Plus Intel plans to change the socket for P4 towards the year-end, and any investment on a P4 platform will be short-term at best, since you will not be able to upgrade to newer processors. Only RDRAM is supported right now on all P4 platforms, but DDR-RAM and SDR-RAM platforms are also in the offing. So go for it only if you’re really looking for that extra edge in performance given by the 1.7 GHz over the 1.5.

Anuj Jain for PCQ Labs