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Telephone Line Problems

Windows Dial-up Networking and most Internet software have an indicator of connection speed. Usually, you can view the speed by moving the pointer over the appropriate icon in the System Tray, as shown in Figure 10.19.

Figure 10.19: Viewing the Internet connection speed.

If you have slow speeds, such as under 38 Kbps with a 56K modem, and/or the Internet connection is frequently dropped for no apparent reason, the problem might be in the telephone line. Hotel room telephone lines often have extraordinarily slow speeds; it is unusual to connect at faster than 19 Kbps from a hotel room, regardless of whether the property is a cheap motel or a four-star property (although some hotels are installing new telephone systems allowing faster connections). There is nothing that the user can do about it unless the hotel has a high-speed network connection, as a small, but increasing number, do. The user should test the connection speed from different residential telephone lines. Chances are that most will be faster than hotel lines are. If, както и да е, the connection speed is very slow or the connection gets dropped frequently in a residence, there might be a problem with either a noisy telephone line or with the ISP. To attempt to rule out the ISP, the user should sign up for a free ISP such as NetZero (netzero.net) or Juno (juno.com) just to test the connection speed and reliability (assuming that the free service isn’t using the same telephone number to connect as the primary ISP is). If they are significantly faster or more reliable, the problem is most likely with the ISP. If they are no faster or better, the problem is probably in the telephone line. This could be a problem with internal house wiring or with external telephone company wiring, или и двете. Have the user check with the telephone company, noting the possibility that there could be a substantial charge in some cases for the telephone company to repair house telephone wiring.

Compatibility

The following factors must be considered to make sure a hard drive will work in a given system:

Form factor: Hard drive form factors aren’t the same as other form factors. They have to do only with fitting the drive in the case, and thus are applicable only with internal hard drives. Desktop and tower computers are standardized for the 3.5-inch form factor, although it is possible to use smaller drives in one of these computers. (We discuss installing a small hard drive in a full-sized system later in this chapter). Laptops take 2.5-inch drives or smaller; check with the laptop documentation or Web site, or remove the drive and look at the label.

Ultra Direct Memory Access (UDMA) speed rating: This refers to the speed of data transfer between system memory and the hard drive buffer measured in megabytes per second and, at the time of this writing, has possible values of 33, 66, 100, и 133. Check the motherboard’s maximum transfer speed and select the fastest hard drive the user can afford. Motherboards can accept any drives rated at their maximum speed or slower.

EIDE or SATA: As of this writing, some new motherboards have connectors for both, but older boards accept EIDE only. SATA expansion cards for PCI slots are available.

Quality

Any time you are purchasing a hard drive that is to be the main or only hard drive in a computer, you should take the following quality indicators into account. A cheap hard drive will provide poor performance in most cases, but might be well suited for file archiving when the files aren’t accessed often.

Here are factors to consider when attempting to purchase the highest quality hard drive for the money:

Warranty: Previously, many hard drives came with a three-year manufacturer’s warranty. More recently, one-year warranties have become most common. Try to get three years if possible.

Buffer (cache memory): This is high-speed memory that is used to store a small amount of data while it is waiting to be read from or written to the drive. As this significantly improves performance of the computer, the bigger the buffer, the better. 2MB is good; 8MB is much better, especially when the user works with graphics-intensive programs such as video editing or games, or other high-stress programs. Drives with less than 2MB of cache will likely provide poor performance.

Platter speed: The most common speeds are 5400 и 7200 revolutions per minute (RPM). The faster the platter spins, the faster data can be accessed and transferred.

EIDE or SATA: EIDE drives are the ones that PCs have been using for many years now. SATAs are just being introduced as this is written. SATA drives perform faster and more accurately than EIDE. An added advantage is that SATA cables are small, making for easier installation and better airflow than the standard ribbon cables used on EIDE devices. The smaller cables also allow for smaller computers.
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