Alienware M15X

To start off, sorry if this is posted in the wrong place. For some reason my laptop will not change the brightness of the screen. The numbers change and go up and down in the brightness meter but the actual screen doesn't get dimmer/brighter. I'm on a Alienware m15x Windows 10. Please help...

I have an Alienware M15X with 6GB ram, intel i5, and Nvidia GTX 260M, Windows 7 64bit Home edition I have it set up so that it's on a hard cover book that's the size of the laptop, with a smaller hard cover book on top of that book to tilt it upwards and allow the two bottom fans to disperse...