Having problem with TN3270 mainframe

Hello!
We are looking for anyone with experience in TN3270 on the mainframe. We are a medium shop with about 2.000 users on z9 2094-504 and now we want to upgrade to TN3270. Are there any impacts on the mainframe like the increase in overhead CPU consumption.
Anyone with the experience of this conversion, please assists us.
We are really stuck.
Thank you…
