2900XT no display

I bought this off ebay about a week ago, now I know they are a bit thirsty with the power requirements so I also bought a 580Watt Hiper Type M PSU to go with it. When I plugged the card into my motherboard the PC wouldn't boot, and, unfortunately it wouldn't with the old card (X850XT) in either, it just sits there with the fans at full speed. So, guessing I had a dead board (a fairly old Asus A8N-E skt 939 board) I bought a nice new motherboard, processor and ram (I was on a budget so I have a P35 Gigabyte GA-P35-DS3L, a Pentium Dual Core E2200 and 2gb Corsair PC6400). This boots fine with the X850 in but the 2900XT still won't work. It just flickers the LEDs on for a split second then appears to trip the PSU out, I have to turn off the power at the wall to get it to reset.

With the above in mind, does it sound like the card is dead, or am I missing something?

Thanks all

Chris