Hey, It is confirmed that the Samsung 4K 28" TN monitor does not work with 4k/60Hz. source: article It appears that 10.9.3 has added support for a few multi-stream (MST) DisplayPort monitors, but as far as I can tell there is currently no support for single stream DisplayPort in 10.9.3. Which means all of those cheap 4K TN panels are a no-go. MST monitors are suffering from their own set of disadvantages and issues as well. I really think Apple has to step forward and solve this with their own 4K Thunderbolt Display asap as nMP owners are buying 4K monitors left and right that are giving them poor result.