More Cache Memory

The new Pentium 4 series has more L2 memory cache, 2 MB, the double of the "normal" series 5 Pentium 4. In theory, the more you have from this memory inside your CPU, the faster it is. So, if we compare a series 5 Pentium 4 to a series 6 Pentium 4 running at the same clock, the series 6 Pentium 4 will be faster, not because it uses the EM64T tecnology, but just because it has more cache memory.

The performance gain depends on the application. According to Intel, this gain varies from 2% to 7%, depeding on the benchmarking software used. This gain can be greater on real-world applications, if it access RAM memory a lot.

Figure 1: Performance gain of a Pentium 4 650 over a Pentium 4 550 (both runs at 3.4 GHz), according to Intel.

Conclusion

It is time for buying the new 64-bit Pentium 4? Only if you are a geek that wants to have a 64-bit ready computer for when the Windows 64 is released. For the average user, it is better wait: a Pentium 4 540 (3.2 GHz) is costing around US$ 230, while a Pentium 4 640 is costing around US$ 320, in the US market.