@Samwel

The 7448 @ 1700 MHz (which will, no doubt, blow away the 1 GHz 7447) is about 550 EUR(!) + taxes per piece in middle quantities. Anyway both, the 7447 and the 7448 become awful expensive when breaking the 1 GHz barrier.
A 1 GHz 7447A or 7448 are both to cool passively, the 7447A starts from about 150 EUR for the 1.3 V version and about 170 for the 1.1 V version. The 7448s @ 1000 MHz are about the same prices (some percent more expensive). Which one peforms better, depends on usage, they are quite colse anyway.
Combined with the TSI 108 the 7448 may offer a signifcantly increased perfromance (200 Mhz FSB), but I haven't seen any real life TSI 108 performance tests yet (I guess it is a good chip). But even that combo (tsi 108 + 7448) is outdated b4 it even rolls out because of the competition of high clocked 744x with the 970FX.
The 2,2 GHz 970FX starts at $185,28 which is about 145 EUR. Compare that to the 550 EUR for the 7448 @ 1.7 GHz. Wow 400 EUR difference!
other to very special applications (and a desktop computer like an Amiga does not belong to this group) it does not make much sense today to use high clocked 744x cpus.
Okay, a 970 maschine will consume more electric power than a 7448 @ 1.7 Ghz (which, at these frequencies, sucks some watts, too). Underclocking of the 970 may change it to a real energy saving chip.
Also note, that the 970 is pretty good in 32 bit mode.
There is close to *no* future in high clocked 744x today. The 8641 is another story, hopefully a successfull, but unfortunately the prices are not public yet.

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