Please check you have not applied any preset while importing the images in Lightroom.
Also, Turn off the Graphics Processor from the Lightroom preferences.
Go to Lightroom Preferences from the Edit menu
Click on Performance tab
Uncheck the Graphics Processor
Let us know if that helps.
Turn off the option to use the GPU in the LR Preferences on the Performance tab.
There are no presets applied.
I'm using Lightroom 5.7, is there a Performance tab in this version? I cannot find it.