iMac G5 does not like Airport extreme card

[MacDan]

Yesterday I installed the Airport extreme card in the iMac. I put it back together correctly and carefully. I booted it and nothing. It would make that spinning hard drive noise and the light would turn on and it would not get past that. Once I took it out, it booted correctly. What's wrong?

My diagnosis: Corrupt card.

2nd opinion: Picky iMac G5.