I have a Power Mac G5 2Ghz Dual Processor, made in 2004.

I'm trying to connect an Apple LED Cinema Display, but this have an Apple Mini Display Port that is not compatible with older models of Mac computers

A seller tell me about this adapter: Atlona (Dual Link) DVI to Mini DisplayPort Converter for Apple 27-inch LED and 27-inch iMac Atlona :: Products :: Converters & Scalers :: Converters with DisplayPort & Mini DisplayPort output :: Atlona (Dual Link) DVI to Mini DisplayPort Converter for Apple 27-inch LED and 27-inch iMac

My questions: Could this adapter resolve my problem?
Could this adapter give me a resolution of 1280 x 768, or higher?.

In advance: Thanks for your opinions!