Actually, from what I hear, the HSF that comes with the boxed 266MHz FSB CPUs is actually pretty good. And it has to be, since it has to cool that egg-frying core that is the Athlon "C". The only thing I suspect that might be bad about the HSF is that the fan might be on the noisy side, and therefore might offend some noise-sensitive people. But it cools well, and some people say that it still does the job even if you overclock your CPU to the limits of the design. But, I suggest a boxed CPU, and if you want a quiet, efficent HSF, there is nothing better than the Sliverado from Noisecontrol. Only problem is that it's around $80 and has to be shipped from Germany. But, if you have the cash to get a 1.33GHz Athlon, then you probably would want to best HSF you can get.
-SammyBoy
Without Evil, there can be no Good. Therefore, without an Intel, there can be no AMD.