motherboard on aspire 6935g?

Hi, I've already contacted Acer in the UK., to ask this question, but all I get in reply, is if you want to courier your laptop for evaluation and so on. Acer do not want for whatever reason to answer my simple question. How much would it cost to replace the motherboard on my Acer 6935G laptop? If they can't just answer a simple question like that, then I'm at a loss as to how to get someone to tell me how much it would cost. The reason, as I've told Acer, that I ask, is that if its very expensive and more than it would cost to buy a new laptop, then I would save 47.50p in courier costs.

Also Acer Thailand, which is where I bought my laptop, have service centres in all major towns and cities. Here in the UK., they have one, in Plymouth. So much for the UK.