Now that OS 10.7.3 finally supports GTX5xx GPUs we sunk some extra effort into these cards. Got a few tips and hints from Netkas that got us moving. I present the fastest Mac Native GPU EVER. GTX580 3GB running in 10.7.3. Card shows EFI boot screens on either DVI port. Also have GTX560 going. Will announce GTX570 separately. Requires external PSU, but this GTX580 kicks AMD/ATI 5870 to curb, leaves for dead, and never looks back.