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%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
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% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
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% Document Info
\author{Glory (gloryo)}
\pdfinfo{
  /Title (components-of-a-computer-system.pdf)
  /Creator (Cheatography)
  /Author (Glory (gloryo))
  /Subject (Components of a Computer System Cheat Sheet)
}

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% Header and Footer
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\fancyhead{} % Set header to blank
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\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Components of a Computer System Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Glory (gloryo)} via \textcolor{DarkBackground}{\uline{cheatography.com/65951/cs/18407/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Glory (gloryo) \\
  \uline{cheatography.com/gloryo} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 30th December, 2018.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
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  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
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\raggedcolumns

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% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{x{2.38896 cm} x{2.58804 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{The CPU}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Key Word}} & {\bf{Description}} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
CPU: {\bf{Central Processing Unit}} & Brain of the computer, processes all data \tn 
% Row Count 4 (+ 3)
% Row 2
\SetRowColor{LightBackground}
CU: {\bf{Control Unit}} & Executes program instructions, overall control of the CPU, holds {\bf{PC}} \tn 
% Row Count 8 (+ 4)
% Row 3
\SetRowColor{white}
ALU: {\bf{    Arithmetic Logic Unit}} & Carries out calculations on data, contains the {\bf{accumulator}} \tn 
% Row Count 12 (+ 4)
% Row 4
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Cache & Very fast memory but slower than registers, holds regularly used data \tn 
% Row Count 16 (+ 4)
% Row 5
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Registers & Memory Location than temporarily holds data \tn 
% Row Count 19 (+ 3)
% Row 6
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PC: {\bf{Program Counter}} & Holds the location of the next instructions \tn 
% Row Count 22 (+ 3)
% Row 7
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Accumulator & Stores result of calculations from the {\bf{ALU}} \tn 
% Row Count 25 (+ 3)
% Row 8
\SetRowColor{LightBackground}
MAR: {\bf{Memory Address Register}} & Holds the memory address about to be used, from the {\bf{address bus}} \tn 
% Row Count 29 (+ 4)
% Row 9
\SetRowColor{white}
MDR: {\bf{Memory Data Register}} & Holds the actual data which has been used or is about to be used, from the {\bf{data bus}} \tn 
% Row Count 34 (+ 5)
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{5.377cm}{x{2.38896 cm} x{2.58804 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{The CPU (cont)}}  \tn
% Row 10
\SetRowColor{LightBackground}
CIR: {\bf{Current Instruction Register}} & Instructions from the {\bf{MDR}} are opened here \tn 
% Row Count 3 (+ 3)
% Row 11
\SetRowColor{white}
Address Bus & Carries addresses from the {\bf{CPU}} to the {\bf{RAM}} or the {\bf{I/O Devices}}, it only goes one way \tn 
% Row Count 8 (+ 5)
% Row 12
\SetRowColor{LightBackground}
Data Bus & Carries data from the {\bf{RAM}} to the {\bf{CPU}} and goes two directions \tn 
% Row Count 12 (+ 4)
% Row 13
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Control Bus & Control signals are sent across \tn 
% Row Count 14 (+ 2)
% Row 14
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{\emph{Fetch}} & Copy memory address from the {\bf{PC}} to the {\bf{MAR}}, copy the instruction in the {\bf{MAR}} to the {\bf{MDR}} and increase the {\bf{PC}} \tn 
% Row Count 21 (+ 7)
% Row 15
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{\emph{Decode}} & The instruction in the {\bf{MDR}} is decoded by the {\bf{CU}}. It will then prepare for the next step \tn 
% Row Count 26 (+ 5)
% Row 16
\SetRowColor{LightBackground}
{\emph{Execute}} & The instruction is performed, usually by the {\bf{ALU}} \tn 
% Row Count 29 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.74195 cm} x{3.23505 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{System Performance}}  \tn
% Row 0
\SetRowColor{LightBackground}
Clock Speed & The {\emph{number of instructions}} a single core can carry out per {\emph{second}} (Hz)\{\{nl\}\}The higher the clock speed, the faster the computer \tn 
% Row Count 6 (+ 6)
% Row 1
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Number of Cores & You can {\emph{independently}} process data. {\emph{More cores}} means {\emph{more instructions}} processed at a time \tn 
% Row Count 10 (+ 4)
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Disadvantages of Cores & Not all programs allow many cores to process data \tn 
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% Row 3
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Disadvantages of Cores & Not all programs allow many cores to process data \tn 
% Row Count 14 (+ 2)
% Row 4
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Cache Size & A {\emph{larger}} cache means the CPU will be faster because it is easier for data to be accessed than it being in the {\emph{RAM}} \tn 
% Row Count 19 (+ 5)
% Row 5
\SetRowColor{white}
More RAM & The {\emph{more RAM}}, the {\emph{more applications}} a CPU can smoothly run, making it faster \tn 
% Row Count 23 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
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\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Von Neumann Architecture}}  \tn
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Primary and Secondary Storage}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Key Word}} & {\bf{Description}} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
RAM: {\bf{Random Access Memory}}, {\emph{Main Memory}} & It can be read or written \{\{nl\}\}It is temporary \{\{nl\}\}All files are stored here when in use\{\{nl\}\}Slower than {\bf{cache}} faster than {\bf{secondary storage}} \tn 
% Row Count 9 (+ 8)
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ROM: {\bf{Read-Only Memory}} & Non-volatile memory \{\{nl\}\}Contains instructions for a computer to boot up ({\bf{BIOS}}) \tn 
% Row Count 14 (+ 5)
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\SetRowColor{white}
BIOS: {\bf{Basic Input Output System}} & Instructions in the {\bf{ROM}} that a computer needs to boot up \tn 
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% Row 4
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Virtual Memory & When the {\bf{RAM}} is full, a space on the {\bf{HDD}} to store data that currently not in use. \tn 
% Row Count 22 (+ 5)
% Row 5
\SetRowColor{white}
Disadvantages of Virtual Memory & Disk Thrashing\{\{nl\}\}Very slow compared to {\bf{RAM}}\{\{nl\}\} The {\bf{HDD}} is not geared to changing data frequently \tn 
% Row Count 28 (+ 6)
% Row 6
\SetRowColor{LightBackground}
Secondary Storage & Where files we want to keep is stored, mainly when it is not in use \tn 
% Row Count 32 (+ 4)
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Primary and Secondary Storage (cont)}}  \tn
% Row 7
\SetRowColor{LightBackground}
SSD: {\bf{Solid State Disk}} & No moving parts- fastest, quickest, reliable, durable\{\{nl\}\}Made from microchips and electrons pass through\{\{nl\}\}High Capacity \tn 
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% Row 8
\SetRowColor{white}
Examples of {\bf{SSD}} & SD Card, USB Stick, SSD \tn 
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% Row 9
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Optical Disk & Laser Light burns marks unto a disk\{\{nl\}\}Cheap, low capacity, Old-fashioned, Portable\{\{nl\}\}Not durable as easily scratched \tn 
% Row Count 16 (+ 7)
% Row 10
\SetRowColor{white}
Examples of {\bf{Optical Disk}} & CD-ROM, DVD-ROM, Blu-Ray \tn 
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% Row 11
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Magnetic Tape & Patterns of magnetism to read data\{\{nl\}\}Noisy due to moving parts\{\{nl\}\}Not very reliable, durable, highest capacity and fast \tn 
% Row Count 25 (+ 7)
% Row 12
\SetRowColor{white}
Examples of {\bf{Magnetic Tape}} & Hard Disk Drive, Floppy Disk, Magnetic Tape \tn 
% Row Count 28 (+ 3)
% Row 13
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HDD: {\bf{Hard Disk Drive}} & High Capacity, Reliable\{\{nl\}\}Between 5400 and 15000rpm\{\{nl\}\}Backing up and transporting data \tn 
% Row Count 33 (+ 5)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}