More than one (3 8840T) on the same LAN

it seems impossible to keep 2 or 3 td8840T router on the same network after a few hours the network goes down, I believe to be the RIP protocol that I can not find how to disable, any ideas?

Hi.
RIP protocal can be changed on the Internet page(Interface Setup---》Internet). Normally, we can just use the default RIP protocal on the modem.
Maybe it is not the RIP protocal issue. Can you post a picture about the network topology and give us some more details about the problem?

The topology network is very simple:
192.168.1.1/24 8840T PC1, PC2, PC3, PC4, PC5 gateway 192.168.1.1
192.168.1.2/24 8840T---> one switch TL-SF1024 --> PC6, PC7, PC8, PC9, PC10 gateway 192.168.1.2
192.168.1.3/24 8840T PC11, PC12, PC13, PC14, PC15 gateway 192.168.1.3

after some ours network goes crazy, switch lights turned on and off all together and ping the IP fails or there is a high latency. The only way to work is to shut down the entire network and restart

All routers and computers are connected on the same switch.

Did the PCs connected to the router carry out high stream internet access? As a soho device, it is not recommend to drive too much equipment for high stream network access.