No need buddy to be so frustrated, we'll fix that :-)

When Disk Utility shows some errors they might be the consequence of Snow leopard being installed from within Leopard 10.5. Did you install your 10.6 from retail dvd in 10.5? If so you might have to reinstall base system from 10.6. I am not absolutely sure but i am pretty much sure that's the cause.

I have 8500GT which i run off the dsdt. I think that aty_init will fix your graphic issue. You shouldn't remove the kexts this card works without any other drivers but the native. You only need the proper enabler, so download aty_init and try with it first.

Regards,
-milanca.

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