ScienceMark 2.0, Pifast
The Dell's Sonoma platform isn't the best for taking advantage of dual-channel DDR2 memory running at 400MHz. There's 6.4GB/s on theoretical tap but the CPU can only make use of 4.2GB/s, and ScienceMark 2.0 reckons that just 2.65GB/s is actually being harnessed. The Pentium 4 Prescott, running at 200MHz QDR, can make do with 6.4GB/s.
Memory access latency will never be fantastic when the memory controller hub is located off-chip, as is the case with both laptops. Still, it's not that bad.
How can a 2.13GHz CPU outperform a 3.6GHz CPU that enjoys greater bandwidth? It's all to do with internal architecture. Oversimplifying for the sake of brevity, the Pentium M can be thought of as the best parts of Pentium 3 and Pentium 4. It has a wonderfully short pipeline, decent levels of L2 cache, and QDR transfers. Intel, it seems, is purposely crippling the Pentium M by keeping it on a 133MHz FSB. It would need a 3.73GHz Extreme Edition Pentium 4 to outpace Dell's Pentium M 770 in the FPU-intensive Pifast test.
