Sorry to hear about that - the W5 is one sweet little machine.
One of the resellers here, Eddie (owner) over at BTOTech, does out of warranty repair work on Asus systems. You can pm him here (geared2play.com) or contact him through their company website at btotech.com for details.
Additionally, you should also check if perhaps the DC board is discrete (i.e., not integrated on the mainboard). If it is, then you might be able to buy it off ASUS eStore for a cheap price, and replace it yourself.
Otherwise, perhaps Eddie will do some soldering and solve the problem cheaply -- on your own, you'd probably need to get a new mainboard which a) may be difficult with an old model and b) will cost 2-300 USD.
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