Hi, The fact the initial probe/attach fails by returning 0xffffffff means the chip isn't "right" on the bus. It's either just not mapped in correctly, or it's "powered off." If it were just asleep, it'd return 0xdeadc0de or 0xdeadbeef or something similar like that. Try AR_SCR (0x4004) and AR_PCICFG (0x4010) . Thanks, Adrian