Badly Manufactured RJ45 Connector

Just last week, our accounting department wishes to isolate their Linux file server whenever they are re-indexing the database of their general ledger program.

In response I installed a network switch where only the server, a client computer, and an up-link/down-link cable is directly connected.

I also need to install an additional UTP cable for the client computer in order to realize an isolated environment that they want.

But when I am installing the UTP cable, the computer can't seem to connect to the DHCP server. I also noticed that the computer's Ethernet speed is 10 Mbps instead of 100 Mbps.

I tried to change the RJ45 connector of the cable (the problem still exists).

The next day I tried to change the UTP cable (using the same model of RJ45). Still the problem exists.

I am using a Belden Cat5e cable and a generic RJ45.

I asked our purchasing department to buy a different model of RJ45 connector (this time a little bit expensive than the one that I am currently using).

When I used the newly bought RJ45 with the same cable that having a problem, it worked.

This is the first time in my entire IT career that I encountered a poorly manufactured RJ45. Most of the cheap RJ45 that I used performed well.

Using a cheap RJ45 connector is not a problem. The only problem would be if the RJ45 is poorly manufactured.