So far, my experience with CRC errors are that they are pretty much 100% hardware related.
Usually cables or bad ports, and one time a whole line of switches had a bad chip on the gig port.
A couple of days ago, I troubleshot a workstation that had a terrible connection. Checking the port stats I found that there were a rediculous amount of CRC errors, almost no collisions and tons of dropped packets. This was on a switch that had only a CU connection to a computer and fiber back to the backbone. The CRCs were on the fiber port. I spent forever troubleshooting thinking I had a bad fiber until I discovered the computer had an extra IP configured. One was in the correct subnet, the other was a 192.168.x.x address. Once I deleted it, everything was great. I checked 24 hours later and the port stats were still perfect.
I'm just hoping someone can explain the *why* of this one. I hate not knowing the reason for something.
