He should be able to overclock a 2.4C Northwood to around 2.8 through 3.0 with the right memory running 1:1. Without high-performance memory, he might get there with less-expensive RAM and running a divider.
THG published some tests recently showing that even improved stock Prescott HSF's were inadequate, because the CPU did a lot more "throttling back" than would be desired. So they recommended aftermarket cooling -- heatpipes, larger fans.
If tgx78 had an ASUS P4C800 or P4P800, he would have implementation of the "Lock-Free" feature in the October, '04 BIOS upgrade. Then he would have a slightly bigger range of over-clock options because he could drop the multiplier of a 3.2E from 16 to 14. Of course, OC'ing that way would again suggest advantages to using DDR433, DDR500 etc. for RAM.
But contrary to earlier conclusions I had made, the thermal design power of the 3.2E and 3.4E with the C0 stepping (candidate for dropping the multiplier) is still 103W in either case. One poster at another forum noted that his load temperature with a ThermalRight XP-90 cooler and Vantec Tornado fan never broke 42C, so an XP120 with a Panaflo Ultra-High Speed 120mm (2,700 rpm -- high speed -- hah!) would give almost the same advantage (shy about 5CFM throughput) as the Vantec Tornado without the noisy disadvantage.
But I would recommend moving across from Northwood to Prescott only if tgx78 is planning to over-clock. The Northwood 2.4C has marvelous OC'ing potential with the right memory, and runs ridiculously cool. the Prescott only shines in over-clocked settings. If you're not going to over-clock, consider a 3.0 or 3.2C Northwood. If you are going to over-clock, try pushing the 2.4C to the limit and get some good, fast memory for it. But if you are going to get the fast memory and run a 1:1 divider, the Prescott 3.2E should perform even better, because the cache-size makes the short stretch between a fast processor and and fast memory even shorter. With the Prescott, I think you'd need a good heatpipe cooler like the XP120, and a Panaflo Ultra HS, SUNON KD1212PMB1-6A, or even a Delta -SHE. With the noisier choices of fans, you can control the fan from the mobo provided the fan-header supports the wattage, and use SPeedFan to keep it quiet at idle processor temperatures and speeds.