Common causes of network slowdowns

What causes slow networks?
The very nature of networking can cause intermittent slowdowns. Network traffic also has a habit of peaking from time to time, which may result in a slowdown. These intermittent slowdowns are to be expected. However, if you determine that a consistent network slowdown or bottleneck exists, the hard part is pinpointing the location of the problem. What follows is a list of some of the causes of network sluggishness. Please remember that the possible causes of such problems are numerous and sometimes occur simultaneously, making it even more difficult to pinpoint where the problem originates.

Network interface card
Network slowdowns often result from a bad network adapter on a PC. Bad adapters have been known to bring down an entire network.

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