Router issues

I recently bought this new router because the old Linksys one finally gave out and stopped working. Once I plugged it in and got it working the wifi works just fine but my computer connected to the router by an ethernet cord now has terrible connection when compared to my old router. Whenever I play a game I am fine for a few minutes but then immediately time out but when I check my internet connection, it shows me as still connected and I can still use the internet. This problem repeats for any game I play and likely for all my internet activities in general. My setup is my ground line connected to a modem, ethernet form modem to router, and then ethernet cord from router to computer. Any fixes or help would be appreciated.