Technology In Action Chapter 5 Evaluating Your System: Understanding and Assessing Hardware
Chapter Topics • To buy or upgrade? • Evaluating your system: • CPU • RAM • Storage devices • Video output • Sound systems • Computer ports • System reliability
Common Byte Measurements Patterns of binary digits represent both the computer instructions and computer data 1 byte = 8 bits 1 KiloByte = 2^10 bytes = 1024 bytes 1 MegaByte = 2^20 bytes = 1024 KB = ~1 million bytes 1 GigaByte = 2^30 bytes = 1024 MB = ~1 billion bytes 1 TeraByte = 2^40 bytes = 1024 GB = ~1 trillion bytes 1 PetaByte = 2^50 bytes = 1024 TB = ~1000 trillion bytes 1 ExaByte = 2^60 bytes = 1024 PB = ~ 1 quintillion bytes 3
To Buy or To Upgrade? • Things to consider: • Moore’s Law • Cost of upgrading vs. buying • Time installing software and files • Needs and wants
The CPU: Processing Digital Information • The CPU is the brain of the computer • Different types of CPUs • Intel and AMD chips: Used in Windows-based PCs • Apple systems use different CPU design • Differentiating CPUs • Processing power • Clock speed • Electricity needed
Evaluating the CPU • What can you do to the CPU to improve performance? • System Clock Speed: • MHz • GHz
How busy is your CPU? • Windows • Task Manager • Performance tab
Upgrading the CPU • Expensive • Easy to install (ZIF socket) • Motherboard compatibility
Today’s Microprocessors • The more powerful a CPU is, the more circuitry is needed to make the CPU work • Such a large amount of circuitry in such a small, concentrated area generates A LOT of heat!!! • Most modern processors require heat sinks and/or fans to keep their temperature in a safe range • Keep your computer in cool, clean area, vacuum it out once in a while, don’t block ventilation vents
Evaluating Other Features • CPU speed is not the only factor in your computer's performance • Amount of RAM • Hard drive speed and size • Speed of video card • Speed of Internet connection
How Much Ram is Needed? • All running processes need RAM including the operating system • PF Usage rate (virtual memory) • if high, need more real RAM • Look at Available Physical Memory to see how much real RAM you have
Adding RAM • will increase system performance • Things to consider: • Type of RAM module • Amount of RAM: • Number of slots - Motherboard • Operating system - how much can it handle? • how many applications running at the same time?
Evaluating Storage • Types of storage devices: • Hard drive • Floppy drive • CD/DVD • Flash memory • All are Nonvolatile storage
The Hard Disk Drive • Storage capacity up to 500 GB • Access time is measured in milliseconds • Data transfer rate is measured in megabits or megabytes per second • Spindle speed is measured in thousands of revolutions per minute (rpm) • Subject to head crashes!
Hard Disk Controllers • controller = electronics that transfer instructions and data to and from the disk • EIDE, SCSI - older • SATA - newer, faster - 3 Gb/sec serial advanced technology attachment • drive must be compatible with controller on motherboard
RAM vs. Hard drive speeds • RAM speed is often expressed in nanoseconds (one billionth of a second) • Amount of time required to access data in RAM • Hard Drive speed is often measured in milliseconds (one thousandth of a second) • Amount of time required to access data on disk • Typical RAM is millions of times faster!
Cache Memory Small amount of memory located on the CPU chip or near it Stores recent or frequently used instructions and data Used for quick access by the CPU Different levels of cache Distance from CPU
Memory / Storage Pyramid • Fastest data access at the top of the pyramid, slower as you go down • Most expensive at the top of the pyramid, cheaper as you go down • RAM / cache = "memory"
Portable Storage • Gives the ability to move data from one computer to another • Types of portable storage devices: • Floppy disk: • Capacity 1.44 MB • CD-R, CD-RW, DVD-R, DVD-RW: • Capacity 700 MB to 9.4 GB • Flash drive and cards: • Capacity 256 MB to 32 GB
Optical Storage • Optical media: • -ROM • -R • -RW • Laser beam • "Pits" scatter laser light equaling a 1 • "Lands" (nonpitted area) reflects laser light equaling a 0
Different Optical Formats • CD vs. DVD • High Density DVD • Blu-Ray • named for color of laser used • most Blu-Ray readers can read other DVDs • higher capacity than HD DVD, 50 GB
Treatment of media • Floppies / Zip Disks / Hard drives • Watch out for magnets! • heat, contaminants • CDs/DVDs • scratches • heat, contaminants • Flash sticks • static electricity - keep cap on when not in use
Evaluating Ports • Ports are used to connect peripheral devices to the computer • Things to consider: • Devices you want to use • Ports needed for the devices
Universal serial bus • hot swapping • 1.1 and 2.0 versions 1.1 = 12 Mbits/s 2.0 = 480 Mbits/s • Powered vs. non-powered • can chain together USB hub USB Connector USB Port
FireWire • High speed transfer of audio and video data (Apple created) • First version 400 Mbits/s, newer version 800 Mbits/s • Comparable with USB in speeds FireWire Port FireWire Connector
Types of Ports • Ethernet • Transfer rates range from 10 Mbps to 100 Mbps; newest 1Gbps • connects computers to LAN or cable modem • created at Xerox PARC 1973-75 Ethernet jack Ethernet Port
IrDA • Uses infrared light waves • Transfer rate of 4 Mbps • being replaced by Bluetooth and Wi-Fi • useful where radio would cause interference IrDA
Bluetooth • Radio waves send data over short distances • meant to replace cables, 1-2 Mbits/s • security risk of instant connection when within range Bluetooth
Make a system more reliable • Clean out your Startup folder • Delete unnecessary files - Disk cleanup • Use anti-spyware and antivirus software • Use the disk defragmenter • Keep software updated • OS, browser, antivirus, device drivers • Keep your system cool and clean
Computers in the Environment • Green Computing • Adopting policies which conserve and recycle resources as well as have minimal impact on the environment • Turn your computer off • Don’t put old computers in landfills • Donate old equipment • Recycle printer cartridges and paper • Buy "Green Star" equipment • Telecommute
Computers in the Environment • Chip manufacture • Computer chips and CPUs are made of silicon • Intel "How chips are made" • Acids, powerful lasers, and hazardous chemicals are used to etch circuitry onto silicon wafers • Chip production takes place in a clean room to keep chips from being contaminated and to keep hazardous materials from escaping • Chip production is largely done by robots to keep from exposing humans to the hazards of the plant