CHAPTER 6: UNDERSTANDING AND ASSESSING HARDWARE: EVALUATING YOUR SYSTEM
Three Types of Technology Users:
1. CASUAL USER: using Internet + office. 2. POWER USER: needs fast powerful processing, storage + creates programs. 3. MOBILE USER: needs lightweight device + long battery life.
Measuring CPU Performance
1. CPU BENCHMARKS 2. CPU USAGE 3. CPU USAGE GRAPH 4. TOWER DESIGN
Types of Storage Drives
1. MECHANICAL HARD DRIVE Hard drive is composed of several coated, round, thin plates of metal stacked on a spindle. Each plate is called a PLATTER. When data is saved to hard drive platter, a pattern of magnetized spots is created on iron oxide coating of each platter. When spots aligned in one direction = means 1, when aligned in other direction = means 0. 2. ACCESS TIME
Selecting a Computing Device
1. SYSTEM EVALUATION Huge number of choices: Tablets, Ultrabooks, Netbooks, 2-in-1s, Laptops, Desktops.
How the CPU works
CPU is composed of two units: the control unit and the arithmetic logic unit (ALU). 1. CONTROL UNIT 2. ARITHMETIC LOGIC UNIT (ALU) CPU fetches data, decodes it, executes the instruction, and stores the results in RAM before fetching next information (Machine Cycle process). Clock Speed, Multiple Cores, and Amount of Cache Memory make CPU different from one to another. 3. CLOCK SPEED 4. OVERCLOCKING Multi-Core Processing = like you would clone yourself to work at a faster paste. 5. LIQUID COOLING 6. HYPERTHREADING
Solid State Hybrid Drives (SSHD)
Combination of SSD + mechanical hard drive. Small amount of SSD storage but can have huge impact on system boot time.
There are different types of RAM such as:
DOUBLE DATA RATE 3 (DDR3): memory modules available in several different speeds. DOUBLE DATA RATE 4 (DDR4): used by high-performance systems. DOUBLE DATA RATE 5 (DDR5): used w/ high performance video graphics cards + fast data transfer rate.
Adding RAM
Easy to add = following installation instructions that come w/ RAM module + lining up notches and push memory module in place. Relatively inexpensive system upgrade.
Your Ideal Computing Device: Moore's Law
New technologies emerge quickly. 1. MOORE'S LAW 2. DYNAMIC RANDOM ACCESS MEMORY (DRAM)
Optical Drives
OPTICAL DRIVES: disc drives using laser to store + read data = data is saved on CD/DVD/BD, OPTICAL MEDIA. Data is read by laser beam w/ pits and nonpits, called LANDS. Blu-ray discs get their name because read w/ blue laser light, means shorter wavelength + focusing more tightly + pack more information on disc. Optical Drives are not as useful as they used to be because everything now is becoming digital = it is not necessary to own one.
Random Access Memory
RAM is volatile storage and ROM is non-volatile storage. RAM so much faster than mechanical hard drive. Resource monitor indicates how storage is used in computer. 1. MEMORY MODULES (MEMORY CARDS) 2. DUAL INLINE MEMORY MODULE (DIMM) 3. PHYSICAL MEMORY 4. SUPERFETCH In 4GB RAM: 1.1GB used to run hardware systems. 0.98GB used to run programs. 17GB used to hold cache data + files ready for quick access. 0.2GB unused.
Solid State Drives
SSD used electronic memory + has no mechanical motors/moving parts = incredibly fast access times. No noise, very little heat, very little power = popular option for Ultrabooks.
PHYSICAL MEMORY
amount of RAM actually sitting on memory modules in computer.
CLOCK SPEED
amount of instructions processed every second.
DYNAMIC RANDOM ACCESS MEMORY (DRAM)
capacity of memory chips.
TOWER DESIGN
changing the shape of case holding the computer parts like Apple's Marc Pro 10 inches cylinder built around triangular collection of printed circuit boards allowing constant air flow from bottom to top, cooling all computer components w/ a single fan.
CONTROL UNIT
coordinates activities of all other computer components.
SYSTEM EVALUATION
evaluates subsystems to see if system is still good enough or should change computer.
MECHANICAL HARD DRIVE
has largest capacity of any storage device + most storage per dollar = more economical device than other options.
CPU BENCHMARKS
measurements used to compare performance between processors. Often published on CPUBENCHMARK.NET
SUPERFETCH
memory-management technique used by Windows, monitoring most used applications + preloading them to system memory so ready to use.
HYPERTHREADING
new set of instructions starting before previous set has finished.
MOORE'S LAW
paste at which CPUs improve, named after Gordon Moore, the cofounder of Intel CPU chip = predicts number of transistors inside CPU increasing so fast it doubles every two years.
CPU USAGE
percentage of time CPU is working.
ARITHMETIC LOGIC UNIT (ALU)
performing all arithmetic calculations + making logic and comparison decisions.
CPU USAGE GRAPH
records CPU usage for the past minute.
LIQUID COOLING
removing heat of computer w/ water-cool system = liquid tube placed in contact w/ heat producing parts of system = liquid picks up heat and carries it to radiator + fan blows across the fins of radiator efficiently dispersing the heat. Sealed-water cooling solutions also available.
OVERCLOCKING
running CPU at faster speed than manufacturer recommends.
MEMORY MODULES (MEMORY CARDS)
small circuit boards holding series of RAM chips fitting in special slots on Motherboard.
DUAL INLINE MEMORY MODULE (DIMM)
small circuit boards holding several memory chips used by most memory modules in today's systems.
ACCESS TIME
time taken by storage device to locate data and make it available for processing = faster than optical drives.