CPU

first off only use one router. reset router to factory defaults. right click in your connection icon and select repair connection. should be good to go.

swap the cable that goes to the computer that is online to the computer that isn't getting any packets. this way you can see if the problem is the computer

You took the wire that went from the router to the online computer and moved it to the offline computer, and it was then able to get online. That means you either the other wire is bad or you have a bad port. So try swapping ports on the router for the offline computer and if that doesn't work replace the wire.

why would you make a thread titled cpu in a cpu forum and ask questions about routers? you got lucky 505090 looked and answered, if you expect answers its best to post in the right section, and its better forum etiquette

then we apologize and move on while learning from our experience. Anywho.

if you can't get to the setup then you never reset to defaults which makes the last step a waste of time

any computer connected to the router can access the web management by putting the following address into a web browser
192.168.1.1

reset to defaults, verify each computer works, verify wiring, verify ports,

if none of that fixes it you have a defective router, but seeing as you have two routers and can't make it work I have to assume your issue is in the router config if you did both, one of the computers, or the wiring