Sorry, I don't know, I'm no more using DD-WRT (my post is old). Unfortunately, each time BrainSlayer fix one bug he creates 2 new ones... I suggest you to ask your question on the DD-WRT forum.

Hi, For your 3 questions the answer is no because the bands are not the same. 802.11N is a standard for both bands...

OK, in this case, try to set a static IP address to one of your wireless client device with the router IP address to its gateway parameter.

You should try this one: http://www.station-drivers.com/index.php/downloads/Drivers/Realtek/WLan/RTL8191SE-RTL8192SE/RTL8191SE-RTL8192SE-Version-2021.0.0223.2012/

Hi, Did you give your router IP address to the "Default Gateway" into the "DHCP Settings" menu ?

Hello, What Realtek driver version do you use and what OS ?