Well when considering the time I'd have this card under load it probably would result in like 50€ per year. When using the card for two years that adds up to 100€...

That's about a third of a new high-end card just for getting a GTX480 together with the fact that if a setting won't run fluid on a HD5870 it in the end also won't run fluid on a GTX480...

Well but I don't want to start praying here: I've told my opinion which needn't be another one's opinion and that's fine with me. Just go ahead and buy what you think is right: The Zotac GTX480 definitely is a fast graphics cards - for me its cons make it unattractive though...