When accessing the network performance, keep in mind that there is a difference between the theoretical speed rating and that of the real world. The difference may be relatively small, but significant, if you have a well set up network. Otherwise, the difference can be extremely large.
As 1GB Ethernet becomes the standard shipped on HP Notebook PCs, however obtaining this throughput is not practical. A throughput of 300 mbs is more likely the maximum obtainable due to hard drive limitations, TCP/IP overhead, and other limiting factors. However, the migration to this standard allows HP to be able to handle future capabilities.
The theoretical rated speed of a network is never achieved in practice, for a number of reasons. Overhead issues mean that not all of the possible capacity of a network can be used for data. External factors such as hardware bandwidth limitations restrict data input and output. Configuration problems can also greatly reduce real-world performance. Finally, it is important to remember that many technologies are asymmetric, offering higher speed in one direction than the other, and the larger number is often the one that is advertised.
Every network has some degree of normal network overhead, which guarantees that you will never be able to use all of the bandwidth of any connection for data. As an example, a 1GB Ethernet line may be able to transmit 1GB every second, but not all of those bits are data. Some are used to package and address the data—data can't just be thrown onto the network in raw form. Also, many of those bits are used for general overhead activities such as dealing with collisions on transmissions. There are natural inefficiencies in any networking technology. There are also other overhead issues and any network transaction involves a number of different hardware and software layers. Overhead exists at each of them, from the application and operating system down to the hardware.