Overclocking In Detail: Pentium 4 With 3000 MHz
The limiting factor with the factory-delivered Intel Pentium 4/2200 is the fixed multiplier. This is how Intel prevents the processor from being easily overclocked. It is impossible to get around this hurdle because a special SRAM register on the CPU contains the multiplier, and this cannot be changed. So this leaves only one option: overclocking the Front Side Bus. In order to measure the performance of an Intel CPU of the future, we used two different platforms - one based on the Intel 845D chipset and the other based on the Intel 850 chipset. With the help of the Gigabyte GA-8IRXP (Intel 845D), we set a record with 3 GHz.
In our last test "Tom's Hardware Speed Project: Pentium 4, Over 3 GHz ," the benchmarks have already shown that, in individual disciplines, the performance did not reach levels that one might expect at such a high clock speed. Here, we can deduce that a DDR SDRAM module clocked at 137 MHz cannot deliver the necessary bandwidth in combination with the Pentium 4, thereby accounting for performance that is somewhat lower than expected. By comparison, our Pentium 4 system with the Intel 850 chipset shows better results in a few of the benchmarks, despite a lower clock rate of 2600 (Pentium 4/2600).
RDRAM Memory: High Speed With 472 MHz
Our RDRAM system (Intel 850 chipset) was able to run at a maximum clock speed of 2600 MHz. The only limiting factor was the AGP bus, which ran at 77.9 MHz in this case. The GeForce 3 graphics card was unable to reach higher speeds. By contrast, the memory ran at 472 MHz, which did not present any problems. In the summer of this year, Intel will introduce the Pentium 4/2533 (19,0 x 133 MHz = 2533 MHz), which will operate with an FSB clock of 133 MHz. Likewise, the speed of the RDRAM memory will also be increased to 533 MHz (PC1066).
