DIAGNOSIS The default picture settings out of the box are often too bright and have low contrast. You're also probably comparing it to a monitor with a different panel type (like IPS vs. this monitor's VA panel), which have different color characteristics.
<FIX You need to calibrate it using the On-Screen Display (OSD). Press the menu button. 1) Go to the 'Color' menu. Start by setting 'Color Temperature' to 'User'. Then, adjust the individual Red, Green, and Blue gains. A common starting point is R=50, G=48, B=52, but tweak to your liking. 2) Go to the 'Picture' menu. Lower the 'Brightness' to around 40-50 (it's often maxed at 100). Raise 'Contrast' to 60-70. 3) For gaming, you might want to enable 'Blue Light Filter' in the 'Extra' menu and set it to a low level (like 10) to reduce eye strain without making everything too yellow.
IF THAT DIDN'T WORK Ensure you're using a digital connection (HDMI or DisplayPort), not VGA. VGA is analog and susceptible to signal degradation and interference, which can cause washed-out colors. Also, check your graphics card settings (NVIDIA/AMD control panel) to make sure the color output is set to 'Full Range' (0-255) instead of 'Limited Range' (16-235), which crushes blacks and washes out colors.
HEADS UP This is a VA panel, which means it has great contrast for deep blacks but viewing angles aren't as good as IPS. If you're not looking at it dead-on, colors and brightness will shift and look washed out. Sit directly in front of it.