using a a500 original power supply ..run the usb after 10 mins crash ..lid off to see if getting to hot same thing .. cant believe usb would pull that much power ..anything in the configs i should check ..maybe a driver is crashing out ? ..unplugged my external floppy ..doesnt crash if it on an usb is not..all a bit weird..power or not power ..thats the question ..
I agree with your beliefs. It wouldn't be the USB causing a PWR drain unless there was something wrong with it or something wrong with your A500 Pwr supply, unlikely for the latter. I guess you don't have a spare A500 Pwr Supply U can try?
Do you have any other external peripherals? Like PCMCIA CF Card, external floppy. If so plug them all in without the USB and see what they do.
You're even using a CF Card Hdd so the machine should be using B.A. power but for the accelerator. When you say crashing what exactly do you mean.. GURU?