Let's say someone set the PC's IP address to the same as the router. You can crash a network if you do that.
Example: Router is at 192.168.1.1. PC is also set to 192.168.1.1. Crash!
At this point I can't tell you it's hardware.
I have a Lenovo 720-18ICB Desktop (ideacentre) - Type 90HT. Recently the integrated network card is causing my modem to crash. CenturyLink has replaced 3 modems in the last 30 days and it all traces back to my computer. The minute we plug the computer into the router I lose all internet and wifi, as soon as I unplug it I get internet back. Is there a way to disable the integrated network card and install a separate pci network/wifi card? If so do I need to disable the onboard NIC/LAN card?

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