Chapter 3, from page 94

Question 1

How can you calculate how many addresses exist for a given address bus?

Answer 1

By knowing the number of wires on the address bus, and raising that number as a power of 2; i.e. 20 wires would have 2 to the 20th power or 1,048,576 addresses. It is commonly called 1M.

Question 2

To correct the actual number that the address lines provided, the International Electrotechnical Committe (IEC) invented special prefixes for binary values. What are they called?

Answer 2

Ibis, represented as 1 kibi = 1024, 1 mebi as 1,048,576, 1 gibi = 1,073,741,824, and 1 tebi = 1,099,511,627,776. They are abreviated as Ki, Mi, Gi, and Ti.

Question 3

Bits and Bytes have different abbreviations. How would you represent 4 thousand bits? 4 thousand byes?

Answer 3

4Kb, 4KB

Question 4

What is the ALU?

Answer 4

Arithmetic Logic Unit, the main number cruncher.

Question 5

Who are the two most common pc CPU providers today?

Answer 5

Intel and Advanced Micro Devices (AMD)

Question 6

The CPUs for mobile devices are provided by whom?

Answer 6

ARM Holdings

Question 7

What is the difference between a pc CPU and a mobile device CPU?

Answer 7

ARM based processors use a simple, more energy-efficient design and the reduced instruction set computing (RISC) architecture.

Question 8

What type of savings do ARM CPUs provide?

Answer 8

cost and battery life

Question 9

Most of Intel’s desktop and laptop processors are sold under what brand names? Server chips are under what brand?

Answer 9

Core, Pentium, and Celeron brands. The high-end server chips are called Xeon.

Question 10

AMD was able to clone Intel chips because?

Answer 10

AMD and Intel signed a cross-license agreement in 1976 giving AMD the right to copy certain types of CPUs

Question 11

Is a tech able to swap Intel and AMD CPU chips today and have them work in the pc?

Answer 11

Not since 1995, when the licensing agreement was cancelled. They are no longer capable pin by pin, and will not work unless they are in motherboard specifically designed for either Intel or AMD.

Question 12

If you purchase a Ryzen computer, you will be using an Intel or AMD CPU? A Celeron? An EPYC? A Xeon?

Answer 12

AMD, Intel, AMD, Intel

Question 13

To reduce the model names of CPUs by utilizing what to show the different variations?

Answer 13

Code Names

Question 14

How can you easily identify all the information about a CPU in a pc, etc?

Answer 14

Use the utility CPU-Z

Question 15

Mobile pc device needs are different from desk top models in what ways?

Answer 15

consume as little electricity as possible, by extending battery charge and creating less heat.

Question 16

How have the engineers designed the CPUs to use less energy?

Answer 16

They run in low power mode and scale up automatically if the user demands more power from the CPU

Question 17

Define throttling.

Answer 17

saving energy by making the CPU run more slowly when demand is light.

Question 18

Define thermal throttling.

Answer 18

when heat rises to the point that the CPU could be damaged, thermal throttling kicks in and cuts back on the available CPU time/space.

Question 19

What is TDP?

Answer 19

Thermal design power, or the amount of heat a busy CPU generates, measured in Watts. This can help determine the kind of cooling needed.

Question 20

Clock multipliers provide what service in the pc?

Answer 20

Multiply the clock speed of the computer to allow the system to run its full max speed. A Ryzen 7 pc runs at 100MHz. With a clock multiplier of x32, the machine can support a full load at a speed of 3.2 GHz.

Question 21

Todays CPUs speed and multiplier are set automatically by using what function?

Answer 21

CPUID, or CPU identifier

Question 22

How many bits does the current EDB use?

Answer 22

64 bits, which allows for 2 to power 60 addressing, or 16 EB (exabyte) of RAM.

Question 23

The primary benefit of 64 bit computing is to support …?

Answer 23

more than 4 GB of memory, the limit with 32 bit processing. (Exam Tip)

Question 24

The early CPUs were called x86 to fit the 80386 processor. What are the current 64 bit processors generally called?

Answer 24

x86-64

Question 25

What is virtualization?

Answer 25

Intel and AMD have built in support for running more than one operating system at a time. Handled entirely by software, with hardware-based support to handle the memory allocation, or updating each OS.

Question 26

The ComptTIA A+ objectives refer to virtualization support as?

Answer 26

The virtual technology CPU feature. (Exam Tip)

Question 27

Parallel Execution does what?

Answer 27

Modern CPUs process multiple commands and parts of commands in parallel.

Question 28

How is Parallel Execution accomplished?

Answer 28

Using multiple pipelines, dedicated cache, and the capability to work with multipple threads of programs at one time.

Question 29

Name the four stages of pipelining.

Answer 29

1. Fetch (data from the EDB)
2. Decode (what type of command needs to be executed.)
3. Execute (perform the calculation)
4. Write (send the data back onto the EDB)

Question 30

How does the pipeline work more efficiently?

Answer 30

each stage does its job with each clock-cycle pulse.

Question 31

A CPU can operate with less than 4 stages. True or False

Answer 31

False. The minimum number of stages is 4 (see question 29).

Question 32

Can a CPU have more than 4 stages, and if so, how?

Answer 32

Yes, with the use of cache. Some have up to 20 stages.

Question 33

Define pipeline stalls.

Answer 33

If a complex command is called in, it may take more than one clock cycle to decode it, causing the pipeline to stop. Current processors use multiple decode stages to reduce the chance of pipeline stalls.

Question 34

The CPU has two main blocks to handle math. What are they?

Answer 34

ALU, Arithmetic Logic Unit to handle integer math, and the FPU, Floating Point Unit, to handle complex numbers.

Question 35

Define thread.

Answer 35

a series of instructions designed to do a particular job with the data

Question 36

Modern CPUs (do, do not) execute instructions sequentially.

Answer 36

do not

Question 37

Why do wait states occur? How are the wait states reduced in a pc?

Answer 37

Because the CPU runs faster than the RAM can supply it with code. To reduce wait states, CPUs come with built-in, very high-speed RAM called static RAM (SRAM)

Question 38

How does SRAM work?

Answer 38

it preloads as many instructions as possible and keeps copies of already run instructions and data in case the CPU needs to work on them again. SRAM is called cache when used in this fashion.

Question 39

L1 cache is located where? L2 cache? Where was the L2 cache eventually placed?

Answer 39

L1 cache is on the CPU. L2 was originally placed on the motherboard. Later L2 was moved to the CPU.

Question 40

What computer parts ran on the frontside bus? On the backside bus?

Answer 40

CPU, MCC, and RAM connected to the address bus and EDB are on the frontside bus. The CPU connection to L2 (on the CPU) is called the backside bus.

Question 41

To keep up with faster processors the frontside bus was doubled and even quadrupled. What do they call this?

Answer 41

double-pumped and quad-pumped frontside buses

Question 42

On the exam, define how the L1, L2, and L3 caches will be described.

Answer 42

L1 is the smallest and fastest cache
L2 will be bigger and slower
and L3 will be the biggest and slowest cache
(exam tip)