Yeah, the Lenovo Y50 listed on Newegg for $1,200 has a slightly slower CPU (100MHz; not a big deal), more RAM (16GB vs. 8GB; for most people 8GB is enough), and a lower resolution screen (1920x1080 vs 3840x2160).
The Lenovo Y50 is in no way capable of running games at 3840x2160 resolution. Even desktop GPU which are much more powerful than mobile GPUs would struggle a lot at such a high resolution. While a super high resolution screen might sound nice, you have to scale things up so that they can be legible on such a high resolution screen.
I played around with several laptops at BestBuy which had super high resolutions and I have to say that I am not really impressed. Like I said you have to scale (stretch) things up to be legible...