Ok, so i have an Asus strix z270e mobo in my rig. my surround speakers are logitech Z506. Right now they are connected via 3x 3.5 aux cords in the the green, black and orange ports. I was gonna use optical but the speakers don't have that port. I feel as if my speakers are not working correctly. What is the correct way to hook them up to my motherboard.
You have connected them the only way possible.
Have you set the speaker levels with a test signal?
Try a different placement for the sub.
Add a soundcard and / or get better speakers. Don't expect miracles for $99.