No display (black screen through gpu)

[aayhaych95]

When connecting the monitor to the gpu there is no display but when i connect the monitor through the mobo there is a display. When using the pc this way every component seems to worked perfectly. The gpu is installed in the second pcie slot as the top slot was damaged. It worked for a few months but one day I loaded up a gamr and went into the graphics menu, there I changed the resolution to the appropriate one for my monitor and that is where the display went blank. Since then no matter which port on the gpu I use there is still not a display. The gpu has power, the fans spin and it was also sent back to overclockers who tested it and said it worked fine. Any ideas on what the problem could be?

Part list:
PCPartPicker part list: https://uk.pcpartpicker.com/list/KLsfXH
Price breakdown by merchant: https://uk.pcpartpicker.com/list/KLsfXH/by_merchant/

CPU: Intel - Core i5-4690K 3.5GHz Quad-Core Processor
CPU Cooler: Cooler Master - Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£24.98 @ Ebuyer)
Motherboard: MSI - Z97-GAMING 5 ATX LGA1150 Motherboard
Memory: Kingston - HyperX Fury Red 16GB (2 x 8GB) DDR3-1866 Memory (£112.87 @ Box Limited)
Storage: Samsung - 850 EVO-Series 250GB 2.5" Solid State Drive (£83.97 @ Amazon UK)
Storage: Western Digital - Blue 2TB 3.5" 5400RPM Internal Hard Drive (£53.40 @ Aria PC)
Video Card: Sapphire - Radeon RX 480 8GB NITRO+ Video Card
Case: NZXT - S340 (Black) ATX Mid Tower Case (£65.48 @ Novatech)
Power Supply: Corsair - CX 600W 80+ Bronze Certified Semi-Modular ATX Power Supply
Monitor: LG - 34UM68 34.0" 2560x1080 75Hz Monitor (£387.97 @ Amazon UK)
Keyboard: Corsair - Raptor K30 Wired Gaming Keyboard (£41.55 @ Ebuyer)

 

[DamagedEngine]

This means that your GPU is not outputting video, and you are running the pc through integrated graphics. You should try to completely wipe and reinstall your graphics card drivers. Use Display Driver Uninstaller http://www.guru3d.com/files-details/display-driver-uninstaller-download.html to delete your current graphics drivers, and then install them again from the manufacturer's website. Make sure to delete the display drivers in safe boot mode and then install the new ones after restarting the PC.