Have been through similar experience myself although on wired connection. I can tell you that you are best sticking to two identical cards and two identical OS. You dont say what your 2 diff OS are? - not that you've got that far. Assuming that your on for example Windows 98 and XP eg and you still want to persevere with your existing hardware and software I would install the card/s and wait for your PC to find the new hardware and then proceed with the on screen instructions. If it doesn't find anything when you boot up it would suggest that either the card is faulty or that you haven't fitted it correctly. Hope you've got some hair left in the end!