To fix this, go into device manager and uninstall the driver and reboot. This should force it to download the newest available from Microsoft, then you should manually update from there using your motherboard's latest network driver that you can get from their website. I tested this cable without router and get 300mbps in my desktop, but when I connect the cable in my router, the lan and wifi connections are limiteds to 100mbps. Mark. correct me if im wrong but by googling the specs for the B450 TOMAHAWK MAX it says it has a Realtek® 8111H Gigabit LAN controller which i google and read that it can support 1GBp/s connections (I might as well be wrong but that's what i think i found) Not sure why you're being downvoted, as MSI's. The FritzBox is connected via a 1 GBit/s ethernet cable to my PC. The problem seems to be the connection between the FritzBox and the Fibre exchange. After that, change speed and. Some customers may report the associated/link speed between their computer and the router is capped at 100 Mbps, thus they cannot get the expected bandwidth from the ISP even though they paid for 500+ Mbps or 1 Gbps.