The modem after connecting the device is stupid, how to solve?

Question

network hardware

I have a dsl-2640u modem (router) that is already about 5 years old. Recently I encountered such a problem when more than 3-4 devices are connected to the modem via Wi-Fi, then it starts to dull, the speed will drop, the delay is up to 2000ms, reboot. The PC is connected to the modem via lan, when only the PC and a couple of devices are working, everything is OK, if more starts to terribly enrage. Who hasn't experienced this? I would be very grateful for your help!

Answer 1

Try changing the power supply. In yours for five years, obviously all the capacitors have dried up.