, OrigamiCar wrote

It gets better - the Windows Genuine Advantage Diagnostic Tool is telling me that Windows is registered and genuine... WTF is going on?

I don't have any spyware or viruses on my system or dodgy software of any description - just basically Windows, Office, Visual Studio, Adobe CS5 and Battlefield....

Sounds like a virus to me. I've replaced hardware, including motherboards, CPUs, monitors, and GPUs several times, and even changed hard drives once, and I've never had validation problems. I would suggest calling Microsoft's technical support and explaining the problem to them. Please see this link for support options.