Before you assume the NIC or cable are "bad", first download new drivers, as that most often will solve the problem.
1. To determine the NIC driver manufacturer
look in your Device Manager section.
2. Go to START > RIGHT click MyComputer >
select PROPERTIES >
3. tab for HARDWARE > click button for Device Manager
4. In Device Manager, scroll down to your Network Interface Card device, double click and get the name of the manufacturer.
5. Go online to the manufacturer site > find DRIVERS
6. Download the driver you need to a desktop folder
7. Go to your desktop folder, find the driver, double click and INSTALL the driver.
8. Restart your computer > it will "see" the new driver and may ask you if you want to use it
instead of the one you have...say YES.
That should solve the problem.
That should give you all you need.
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