Several situations:
1. You block the motherboard's own network card in the BIOS. If you restore the motherboard bios settings
2. It’s not that your network card project does not have one, but that you don’t have a driver, so the yellow exclamation point item of PCI DEVICE is displayed in the device manager. In this case, you can just use the network card driver that comes with the motherboard to drive it.
3. This situation is also true, but it does not happen often, that is, the network card on your motherboard is burned, so you can't recognize it.
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The above is the case where the motherboard comes with its own network card.
Below is the PCI slot network card
4. The network card is not plugged tightly
5. The network card has no driver
6. The network card chip is damaged
1. You block the motherboard's own network card in the BIOS. If you restore the motherboard bios settings
2. It’s not that your network card project does not have one, but that you don’t have a driver, so the yellow exclamation point item of PCI DEVICE is displayed in the device manager. In this case, you can just use the network card driver that comes with the motherboard to drive it.
3. This situation is also true, but it does not happen often, that is, the network card on your motherboard is burned, so you can't recognize it.
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The above is the case where the motherboard comes with its own network card.
Below is the PCI slot network card
4. The network card is not plugged tightly
5. The network card has no driver
6. The network card chip is damaged