On my DD-WRT setup I am able to set one of my interface ports to "VLAN" with my WAN port.

This allows me a port on the back of my router that skips the router completly and is just like connecting to the WAN.

Trying to decipher what is going on with the DD-WRT single check boxes that allow this under the VLAN's tab it shows 16 VLANS. 0 is connected to ports 1 2 3 and a bridge VLAN 1 is connected to the WAN port and port 4.

This allows port 4 to bypass the router completly and is like plugging into the wan.

Ive searched and tried all sorts of stuff without luck.

I am starting off with the default config when you reset a 750G

So you just want to bridge ether4 with your WAN port? In this case you don't need any VLANs.... Make sure you change all the IP address and DHCP or PPPoE config to the bridge interface.

Create a new bridge...
/interface bridge add name=WAN-bridge

Add the ports to the bridge
/interface bridge add bridge=WAN-bridge interface=WAN
/interface bridge add bridge=WAN-bridge interface=ether4

Thank you...

I think thats working. I need to check more..

So I used Winbox and created a bridge.

I used Winbox and went to interface and to the port I wanted to bridge and removed it from being a slave by choosing none.

I then used Winbox to add my WAN port and my Port 5 to the just created bridge..

I then changed by DHCP client to use the bridge and changed my Firewall NAT to use the bridge.

Seems to work. I still need to test my Port 5 and make sure its directly connected to the WAN..

I am slowly starting to understand this stuff...

Will doing this effect performance at all ?

Perfect...

This works and does not seem to effect performance at all..

I like have a port on the back of the router that is tied directly to the WAN side.