First of all, before I start, here are the system specifications (that might be relevant to this issue):
Processor: Intel Core i5-6500 (3.2GHz)
Motherboard: ASUS B150M-A/M.2
Graphics Card: Gigabyte AMD RX480 w/4GB of GDDR5 VRAM
Power Supply: Cooler Master Elite 550 Ver.2 (550W)
HDD: Barracuda ST100DM010 1TB SATA 6GB/s 64MB
RAM: 1x8GB Corsair Valueselect DDR4
Monitor: LG 22M38D-B 22in 1920x1080p LED
Now on to the actual problem.
When I turn the computer on, it works perfectly fine (to a complete novice); decoration lights are on and the fans are turning.
However, connecting the monitor to the computer with a DVI-D cable (which is the only one that works, as the monitor only accepts DVI-D and VGA) from the graphics card (which supports HDMI, DVI-D, and DP) doesn't seem to do anything. Firing the whole system up (Monitor, computer, keyboard, and mouse) leads to the computer running as usual, with the monitor only displaying "Checking Signal..." until after a while it displays "D-SUB NO SIGNAL". I've searched this up and the only results are to remove, clean, and reinsert the ram and taking out the CMOS battery for 10 minutes then reinsert it. I've the remove-clean-reinsert method, but nothing's changed. Reading the comments of a video that took out the CMOS battery on the motherboard along with the RAM reinserting apparently tells me that it will cause a lot of restarting, so I'm scared to try it. I've also replaced and reinserted the graphics card, CPU and verifying if the cables I plugged in were in the correct socket.
If there are any solutions that I haven't found, I'd be more than happy to hear them.