I connected my new Sony 4k TV up to my Windows 7 computer with a new graphics card to support 4k resolution. Everything is working very well except that all the Menu fonts are tiny. There is an adjustment under preferences but nothing changes. I did close and re-open LR as instructed.
Lightroom 5 the font sizes changed to Small, Medium, Large 150% and Largest 200% (the last one is what you want for QHD displays.)
LR4 only had 3 font size choices (Auto,Small and Large) and does not support QHD/4K displays.