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Note: The questions on the exam will be based on variations of the following pool of questions and exercises in Unit 1 and Unit 2.
Benchmark is tests different computers
The main task of benchmarking is to testing Processor, Multimedia, Memory, Display Adapter, Hard disk, CD and Network of the computer
Benchmarking show user comp characteristics and can made personal rating for comp.
After testing computer with Benchmark software, user can see slow points (bottlenecks). At benchmarks analyzed diagram.
| Amount | Prefix |
| 220 | mega |
| 230 | giga |
| 240 | tera |
| Binary | Decimal |
| 1 1011 | |
| 1111 1100 | |
| 11 0011 | |
| 1010 0101 |
Because comp use binary system and 2 in power of 10 is 1024.
Sellers approximate 8 to 10 bits.
2 in power of 40, it is more than 1 terabyte.
Choose among the following components to label the image:
Motherboard
Power supply
BIOS ROM Chip
Cooling fan
Expansion slot
RAM chip
Expansion card
Disk drives
Chipset
IDE cable
Ethernet cable
PCI bus
Describe the functionality of each of the following components (in 2 sentences or less):
reduction of the space required for storage(of binary data) by an algorithm which converts the data to a smaller number of bits while preserving the information content.
To reduce the file size.
Replace common sequence of character with a single codeword,or symbol that points to a dictionary of the original characters, or to the original occurrence of the word.
A kind of compression algorithm which replaces sequences ("runs") of consecutive repeated characters (or other units of data) with a single character and the length of the run. This can either be applied to all input characters, including runs
of length one, or a special character can be used to introduce a run-length encoded group. The longer and more frequent the runs are, the greater the compression that will be achieved. This technique is particularly useful for encoding black and
white images where the data units would be single bit pixels.
WINZIP
IPS is instructions per second which is a rating of how many instructions can be executed by a processor in a given second.
IPS is a better determiner of computer performance.
A high Hz can indicate that the IPS is high, but they are not directly proportional, but can never be inversely proportional
An instruction can take a variable amount of cycles or partial cycles. Thus, a computer can execute instructions more quickly than another computer because of this.
The system clock sends out pulses at regular intervals to set up the timings for all timed system activities, such as determining the Hz of a processor.
Just as decimal numbers can be represented in exponential notation so too can hexadecimal. By convention, the letter p represents times two raised to the power of, whereas e serves a similar purpose in decimal. The number after the p is decimal and represents the binary exponent.
Because it will takes more digits to express a value in binary notation than in hexadecimal notation, we have adopted hexadecimal notation as shorthand for binary so that we can express values more concisely.
Hexadecimal,
| Decimal | Hexadecimal |
| F | |
| BF | |
| EE | |
| 6B | |
| A3 | |
| DD |
Bitmap is composed to a grid of dots, and the color of each dot is stored as a binary number.
Vectored images consist of a set of instructions for re-creating a picture. Instead of storing the color value for each pixel, a vector graphic file contains the instructions that the computer needs to create the shape, size, position, and color for each object in an image.
Bitmap tends to be more photo-like in quality. Since the bitmap is composed of pixels, so is the photo.
Vectored images.
Powerpoint, photoshop, coreldraw
Stands for input/output device.
Digital camera, printer, speaker, keyboard.
Users take pictures with digital camera. It is stored in digital form, and can be uploaded onto a computer.
The printer can print images or files. Keyboard is used to type data into computer. The speaker is the output device to enable the voice.
Magnetic disks, with the exception of floppy disks, can be written and read faster than optical disks. Most hard disk drives offer greater capacity than any currently available optical device. And usually the writable of magnetic disks is unlimited.
| Type of Media | Storage Capacity |
| double density floppy disk | 720 KB |
| high-density floppy disk | 1.44 MB |
| Zip disk | 100 MB or 250 MB |
| Jaz disk | 1 GB or 2 GB |
| hard disk drive | 20-80 GB |
Before data is stored, the particles on the surface of the disk are scattered in random patterns. The disk drives red- write head magnetizes the particles, and orients them in either a positive or negative direction. These patterns of magnetized particles represent 0 and 1 bits.
The observation made in 1965 by Gordon Moore, co-founder of Intel, that the number of transistors per square inch on integrated circuits had doubled every year since the integrated circuit was invented. Moore predicted that this trend would continue for the foreseeable future. In subsequent years, the pace slowed down a bit, but data density has doubled approximately every 18 months, and this is the current definition of Moore's Law, which Moore himself has blessed. Most experts, including Moore himself, expect Moore's Law to hold for at least another two decades.
Processing power (speed) doubles every 12-18 months. Storage capacity of RAM doubles every 12-18 months.
User expect to pay for a computer today that is twice as powerful as the computer that is now 18 months old approximately the same amount of money paid for the old computer.
Parkinson's law of data states that data expands to fill the space available.
Optical media are more durable. They are not ruined by dust or moisture, nor are they vulnerable to electrical damage (however, they can be damaged by physical damages such as scratches). Optical media's MTBF rating (average life expectancy) ranges between 30 and 300 years, while magnetic media utilize magnetic properties that have a MTBF of about 3 or 7 years.
Optical media are less expensive per MB than magnetic disks.
| Type of Media | Storage Capacity | Number of Times It Can Be Written To |
| CD-ROM | 650-700 MB | |
| CD-R | 650-700 MB | Write once |
| CD-RW | 650-700 MB | Many |
| DVD-ROM (SLSS) | 4.7 GB | Read only |
In the optic readable CD-ROM, the data storage consists of millions of indentations burnt into the lacquer coated, light reflecting silver surface. The burnt dents reflect less light than the shiny surface. A weak laser beam is sent to the disk through a two-way mirror and the sensor registers the difference in light reflection from the burnt and shiny areas as zeros and ones.
First, DVDs have narrower tracks, so they can squeeze more tracks onto the same size disk. Both CDs and DVDs are read using light from a laser. But, the CD laser is red, while the DVD laser is blue. Red light has a longer wavelength than a blue light. The blue laser is thus able to produce a smaller beam, allowing it to focus on the tinier tracks of the DVD. The second way that DVDs achieve increased capacity over CDs is by using multiple layers of tracks. The blue laser is not only narrower, but also more powerful. Its beams can penetrate the plastic and focus at different depths.
Signifies the number of dots (pixels) on the entire screen.
800*600,1024*768
The number of distinct colors that can be represented by a piece of hardware or software. Color depth is sometimes referred to as bit depth because it is directly related to the number of bits used for each pixel. A 24-bit video adapter, for example, has a color depth of 2 to the 24th power (about 16.7 million) colors. One would say that its color depth is 24 bits.
24bits,32bits
1024*768, 32bits RAM = 1024*768*32/8 = 3145728 Bytes,about 3M
From the equation above we know,the capacity of RAM needed to display depends on resolutions and the color depths
Consider the following devices:
Mouse
Printer
Keyboard
Modem
Speaker
Digital camera
Ethernet jack
Monitor
For the following questions, indicate which device(s) should be plugged in which port(s) A-H shown in the diagram below.
PS/2 port
Serial
USB port
Serial
DB-9 (serial) port
Serial
Parallel (printer) port
Parallel
Random access memory (RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order with a worst case performance of constant time.
RAM speed is measured in MHz, PC rating or NS (nanoseconds).
SDRAM stands for Synchronous Dynamic Random Access Memory. SDRAM is a type of
semiconductor memory that is used to increase how many instructions your computer's processor
can process in a given amount of time. This is an improvement over the older DRAM or
Dynamic Random Access Memory.
You will often hear computer users refer to any RAM, includi SDRAM, when talking about computer speed. Any time you run a program on your computer like a word processing program, game, or Internet browser, your computer's processor loads the executable file (.exe) for that program from the hard drive to the RAM. The larger the program, the larger the amount of RAM it will need to run smoothly. Programs such as Microsoft Office Power Point or state of the art games will take a huge chunk of RAM to run. This means any other programs may slow down or stop completely.
If you take a look at your computer right now, you probably have an antivirus program running, your Internet browser, and a few other programs. Each one of those little icons on the bottom of your screen is using RAM.
Most newer computers will come with 2 to 4 Gigabytes of SDRAM already installed so you won't have to worry about it at all. If you have an older computer, adding RAM is always a great first step to an upgrade.
Most software you can purchase will show you the minimum RAM needed for the software to run efficiently. You should always double-check the packaging of any software to make sure your computer meets or exceeds the recommended amount of RAM.
Volatile memory, also known as volatile storage, is computer memory that requires power to maintain the stored information, unlike non-volatile memory which does not require a maintained power supply. It has been less popularly known as temporary memory.
Most forms of modern random-access memory (RAM) are volatile storage, including dynamic random-access memory (DRAM) and static random-access memory (SRAM). Content addressable memory and dual-ported RAM are usually implemented using volatile storage. Early volatile storage technologies include delay line memory and Williams tube.
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