Is this normal Wi-Fi behavior topic

If I enable both 2.4ghz and 5ghz in my router (d-link dir-850L) my T800 will only connect to 2.4ghz. If I enable only 5ghz it will connect to 5ghz. This happens with stock, modified stock, and CM ROM. I'd prefer to enable 2.4ghz for backward compatibility with older devices, obviously.