Merci Nobug, d'ailleur je viens de recevoir un mail d'Asus Shangaï:
Dear Customer,
Thanks for choosing ASUS tek.
Our V8420 supports both AGP 3.3V and 1.5V, and it can adjust the working Voltage regarding the voltage key of the AGP Slot on the
motherboard. On the motherboard that only supports 1.5V, the card will automatically set the working voltage to 1.5V.
Best Regards,
ASUS Customer Service Center Shanghai