Pi-hole isn't a proxy, it doesn't go in between your network and the router. It hangs off the router just as another client. The only traffic it sees is DNS queries and responses that are directed to it on the local network.
Okay. That information is starting to sink in. So I guess the issue I have is now that I can't use a Raspberry Pi because it doesn't have a LAN gigabyte connection to go from my router to it for me to use Pi-hole on so I've got to do some research on a device that broadcasts Wireless N, that supports an OS that supports Pi-hole.
This doesn't replace your router. You don't need gigabit.
You currently have your clients set up to use DNS. Take for example Google. The DNS points to 8.8.8.8 and all you send to Google is a DNS query. You don't send your entire network traffic through the DNS server at 8.8.8.8.
Replace 8.8.8.8 with 192.168.0.115 which points to a Raspberry Pi sitting on your local network. You tell your clients to use 192.168.0.115 for DNS resolution and that's it. No forwarding traffic, no routing, just pure DNS. 100Mbps interface is more than enough for that.
Wow. I am an idiot and thank you for pointing that out to me. I've been sitting believing Raspberry Pi doesn't do gigabit when it does. I get what you are saying about DNS and you are thinking about DNS and I'm not. I'm not worried about that. I'm worried about bandwidth and I know now I shouldn't.
It's actually a quite common misconception. When people think ad-blocking they think that the ad-blocker needs to be in the middle of the conversation between client and server, and for most solutions that is true. We are different in the fact that we only operate on DNS traffic. So the hard requirements are a lot lower and places that Pi-hole can be installed are much greater.
Personally I use NanoPi Neo devices when I install Pi-hole and they run just fine with Armbian as the OS of choice there.
Well, I already have a Raspberry Pi 3 Model B v1.2 but if I do decide to use another device, I will look into NanoPi Neo devices. Which Neo do you recommend since I see 6 different versions?