The [Nokia N9](http://www.gsmarena.com/nokia_n9-3398.php) (64GB version) goes for under €600. It's a bit of a niche phone since it has an uncommon operating system (MeeGo, a Linux distribution).

- 3.9" AMOLED 16M display (251 dpi)
- 1 GHz Cortex A8
- 8 MP, 3264 x 2448 pixels, Carl Zeiss optics, autofocus, dual LED flash

For the rest of the specs, see the link. The screen is slightly smaller than requested, but it's not that big of a difference. I think it's definitely a noteworthy candidate.