Had system working great with Snow Leopard but no wifi! so I tried to replace the Wifi card with a Dell DW1390. Easy installation but as soon as I switched back on I get... "Memory allocation error! Addr=0xdeadbeef, Size=0x0, File=ati.c, Line=394 This is a non recoverable error! System HALTED!!! " I tried inserting the original card back in but I get the same error! Any ideas?