Speed test on PC is different from the speed test on the router (2000 Mbps~ versus 1500 Mbps~)

My Configration: Connection: FTTH 2.5 Gbps Router: Asus AX88U Pro (with 2.5 Gbps WAN and 2.5 Gbps LAN) 2.5 Gbps network card on motherboard (MAG Z790 TOMAHAWK MAX WIFI 7) with updated driver I have tried two Cat7 cables and one Cat6, using the same speed test service (Ookla) against the same server, but on the router, I get over 2000 Mbps, while on the PC, I don't exceed 1500 Mbps. I have set the network card speed and duplex to automatic and then forced it to 2.5 Gbps, but the result hasn't changed. Below are some screenshots. Speed test on PC (tried multiple times) Speed test on router The e

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