Yes, it produced a menu. I could pick 50hz or 60hz at 1080p. At 2560x1440, it's locked to 60hz. Still, pretty happy to get 1440p at 60hz. Again, this is ONLY on the non-4K adapter. On the 4K adapter my results are far, far worse, but I can't tell you why.
So I'll stick with 1440p @60hz for now. Bit of a bummer the 4K Fit just doesn't work properly with 2014 minis.
So what you're saying is you couldn't pick 60 Hz from the menu with the Fit 4K attached?
I can't get 2560x1440 at 60 Hz on mine either, still stuck at 15 Hz. Might as well keep running mine in 1680x945 HiDPI at 15 Hz, looks great on the Retina iMac.
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I'm considering ordering a Mac mini for headless use. Has anyone had luck running 1024x768 HiDPI at a normal refresh rate? The screen shots above show 17hz.
Thinking of trying to run it at native resolution on my retina iPad.
I find the lag to be much worse over WiFi than Thunderbolt Bridge, so I would suggest running it at a lower resolution anyway. Or just use a physical display, keyboard, and mouse.