Looks like the power supply is 'universal' and the specs look the same. Hopefully it'll perform how you need it to.
Yeah It is my own fault really. I just assumed it would perform as the 7800N that everyone went on about. Clearly this isn't the case. Never mind, I should be able to get some money back from it as it still has one years Billion warranty too.
Thinking about it last night, I'll probably be best to purchase in the UK for returns purposes. I'm best to buy things from the states that I can't break or whatever.