For the record: this card has a ACX111 chip, supported by the ACX100/111 driver. I managed to make it work under Debian yesterday.

As today, this card works pretty well but there is still a lot of bugs in the driver. So it is usable, but be aware that once day you may have to do an rmmod && modprobe.

Furthermore, it seems that this card is very sensible about the PCI slot you put it in. At least, putting it in another PCI slot than the last one of my Asus P4P800, makes it act weirdly: PCI id not the same, error writing the firmware, and so on.