Thanks robgeb, and thanks freeman303 for asking.
I only just realised that these machines are virtually the same. see http://forum.notebookreview.com/showthread.php?t=43766
where gweilo8888 says:
It is more than just using the same chip - the Ferrari 4000 and TravelMate 8100 are basically the same laptop, just one's Intel-based and one's AMD-based. (If you look at documents from Acer to have the laptops certified, they go so far as to state that:
"Models ZF**, TravelMate 81**, and Ferrari 4*** are identical to each other except for model designations for marketing purpose."
If you're wondering what the "ZF**" is, that's the OEM name. These two laptops were designed by Acer, but manufactured by Quanta, and that's Quanta's model numbering schema. The TravelMate 8100 is the Quanta ZF1, and the Ferrari 4000 is the Quanta ZF3.