Comparing Printers

Below is a chart comparing printer types. The cost and quality measures are relative to each other.

Printer Technology	Price of Machine	Price of Supplies (for example, ink and paper)	Quality of Text Printouts	Quality of Image Printouts	Speed	Typical Usage
Ink (black/white)	$	##	**	*	medium	Home
Ink (color)	$	###	***	***	slow	Home
Dye-Sublimation	$$$$$	####	**	****	slow-medium	Photo labs
Laser (black/white)	$$-$$$$	#	****	*	fast-very fast	Small Office/Home Office
Laser (color)	$$$-$$$$$	##	***	** - ***	medium-fast	Office (for example, marketing department)

Table 1 Comparison of printers

In general, you should select a printer based on your usage. For a home office, a laser printer will offer the lowest cost per page (cpp) of all printers, making them economical in the long run, but with a large up front cost for the equipment. But, if you will not be printing many pages at home, you might want to consider getting an ink-jet printer.

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2.3 Storage Devices

Why does a computer need to store files on a hard disk drive? Why not keep everything in RAM memory? There are two reasons. The first reason is that RAM memory is volatile: the data is represented by electric charges and is lost when the power is turned off. A hard disk drive stores information as magnetized patches on the disk surface, so the data persists even when power is removed. The second reason hard disk drives are useful is that they have a much larger capacity than RAM. A typical personal computer today will have at least 128 megabytes of RAM memory and 40 gigabytes of disk storage. That disk capacity is more than 300 times what can fit in RAM! So, even though hard disk drives are slow as compared to RAM, they are an important component of your computer system.

Reading Sequence: Parsons/Oja, Chapter 2-Section C. Learning Goal: Knowledge of the variety of storage media, magnetic and optical, used by modern computers. 2.3.1 Disk Controller Interfaces. Learning Goal: Knowledge of the IDE (Integrated Drive Electronics) interface used for connecting disks to PC-based computer systems. (The disk controller is responsible for the physical operation of the drive mechanism and the transfer of bytes between the drive and main memory.) 2.3.2 Mass Storage. Learning Goal: Knowledge of basic differences among types of mass storage, comparing each storage type with the others.

                        

Assessments: Multiple-Choice Quiz 6

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2.3.1 Disk Controller Interfaces

• IDE Interface

• EIDE Master/Slave

There are many common interfaces to connect a storage device to a computer. We have discussed Universal Serial Bus (USB) and FireWire in section 2.2.1 Connecting Peripherals. Another common interface not yet discussed is Integrated Drive Electronics (IDE). An IDE (Integrated Drive Electronics) is the interface that enables data to transfer between storage devices and the chipset. IDE is designed specifically as disk interface whereas USB and FireWire can interface with other devices besides storage devices such as digital cameras and printers.

Below is a diagram illustrating the disk controller, the IDE interface, and the storage devices with respect to other components in a computer system. Note that the functionality of the disk controller is often integrated into the chipset.

Figure 1 Disk controller interface and storage devices