I am setting up one of my older routers as a VPN client for PIA. I want to set up my Windows 8 machine to be connected to the VPN router for some programs, but connected to an encrypted line for other programs, like games, (and sometimes YouTube).
I’m planning on being hardlined to both routers, since my motherboard has two ethernet ports, but my question is how do I set up my computer to use one connection for certain programs, and the second connection for others?
I couldn't tell you exactly how to do it with dd-wrt, but you should be able to create firewall rules in the router which will send certain traffic to a certain gateway. This would be based on ports also you could use the vpn for everything on 80 and 443 for Web traffic and have everything above 1024 use the regular connection which won't be encrypted.
This way you only need one router. I have a set up like this but I use pfsense so I can't tell you specifically how to set it up.
Alternatively you could create a proxy which uses the vpn, the set programs to either use the proxy or not, that way you can direct the traffic based on the application rather than the port.