@Massacher Go through this FAQ Q2 and Q3. 733 mbps on 5 GHz is the theoretical maximum. In reality because of a wireless connection nature (half-duplex), 866mbps bandwidth is normal.

Configuration backup of TD-W9960 - here. Configuration backup of TP-Link wireless routers - here.

@Gtrem That's easy - check this post.

@Halfbob Actually, you can do that - just make sure you have replaced both - check this thread.

@Gtrem In general if you don't have any issues with the internet connectivity there's nothing to worry about. Ther's no documentation on the system log messages but you could look at this thread for...

@GailCurtis Go through this thread for troubleshooting your issue.