I am sorry, but I seemed to have thrown the dongles out after I got disenchanted with them. I am pretty sure it has burnt out since it has got that funny burnt smell, and it certainly did heat up.
I did blame the first burnt out one on USB voltage problems, as I put the key into a very old machine, one of the first ones that came with a USB port. The key toasted the motherboard USB port as well.
So I tried the second one on a new machine, which I have tested other USB devices on. And the same thing happened. However, I did not physically measure the voltage. In any case, I would expect the dongles to be a bit more tolerant than that, given that they are expected to be plugged into different machines.
From the other posts, it seems that some USB keys are at least working. Maybe it's just my batch that's bad. Should have gone for the refund
I have heard about notebook and USB voltage problems, like the Libretto L2 that I have. But it is a case of underpowering rather than overpowering.
Sorry I can't be more helpful, but thanks anyway.