Are there technical and/or other considerations that should be regarded in deciding which of these two CPUs to select for a new build? Why are there two different versions of the same chip, seemingly with the only difference being the power and heat differences. The 95 Watt chip has a maximum temperature of 71 degrees C, while the 125 Watt chip has a maximum temperature of 62 degrees C. All other technical specs seem to be identical, although I don't clearly understand why the lower power chip would have a higher temperature tolerance. So, ... why wouldn't the clear choice be to always go with the lower power chip?
What other things should I be thinking about when making a choice? AMD recommends essentially the same motherboards for either chip.
They are the same chip but a different stepping. When yields get better they also tend to be able to get a better stepping in with bug fixes and better thermals as well.
When Intel released the Q6600 it was a 125w TDP CPU with the B3 stepping. They worked out some bugs and some thermal spots and the G0 stepping was a 95w TDP CPU. And you can use the same mobo for both CPUs.
I would go with the 95w TDP. It will run cooler and also be able to OC better while also giving about 1-2% better performance due to the later stepping and all at the same price.