Dell XPS 15 9530

Hi, 

I recently got a dell xps and the product quote did say the laptop was shipped with QHD however when trying to change the display settings to the 3200x1800 resolution, thats not available. the max setting is 1920x1080.

The specs are the following:

4th Generation Intel® Core™ i7-4702HQ processor (6M Cache, up to 3.2 GHz)
Windows 8.1 Pro (64Bit) English
15.6 inch LED Backlit Touch Display with Truelife and QHD+ resolution (3200 x 1800) (this is what it says..)
16GB2 Dual Channel DDR3L at 1600MHz
1TB 5400 rpm SATA Hard Drive + 32GB mSATA Solid State Drive
NVIDIA® GeForce® GT 750M 2GB GDDR5
4.44 lbs

Is there anything i'm missing ? maybe i don't have the right dell stuff installed or what?

Thanks