Hardware 101 Flashcards
Form Factors
The Motherboards have different shapes and sizes. Most popular are:
ATX (Advanced Technology Extended):
- standard form factor
- 12 x 9.6 inch
- 1995, Intel
micro ATX:
- 9.6x9.6
- cheaper than the ATX
Motherboard
‘mobo’ or ‘mainboard’
basically a circuit board
What does a motherboard have?
North and South Bridge (chipsets):
North: communication for the fast boys: CPU, GPU, RAM - now done almost entirely by the CPU
South: communication between the hard drives, I/o etc. - now done PHC (Platform Hub Controller)
BUS slots (extensions such as the GPU)
CPU socket
SATA connectors, M.2 slots, memory slots
Also has a Clock Generator that’s responsible for synchronisation in the PC.
I/o interfaces
I/O interfaces
USB (Universal Serial Bus)
Integrated Video: HDMI, Display Port, DVI, VGA
Network Internet Card
Integrated Sound Card
BIOS
Basic Input Output System (Firmware)
stored on the BIOS chip
non-volatile memory (memorysaved when there is no power)
initialises the computer hardware, checks the peripherals
P.O.S.T
Power On Self Test - the computer must past this test (initialised by the BIOS) in order to boot up
CMOS chip
System settings first set up by the user that are saved when the PC is turned off
Volatile
Data & time, boot sequence, hardware settings
It’s powered up by a special battery called the ‘CMOS battery’
UEFI
Unified Extensible Firmware Interface
replaced the BIOS
user-friendly, graphical interface
CPU
Central Processing Unit
understands machine code (1s and 0s)
Performs all of the arithmetical operations
Performance based on: number of cores, clock speed, size of registers, pipeline length, type
Cores
- processing unit
- ALU (arithmetic- logic unit)
- CU (control unit) - directs operations to the processor
- registers
Clock Speed
How many instruction per second (Hz)
The value which is initial (came from the factory) can be altered with (overclocking)
Cache
Memory which is on the CPU, storing often accessed data and instructions. Fast cause doesn’t need constant power (refreshing). There are different levels, which are checked for instructions before checking the memory (RAM). L1 (8-64KB)-> L2 -> L3.
Size of registers
How much data can be processed per clock cycle
Pipeline length (not sure)
One instruction after the other so I guess pipeline length specifies how many instructions can be fit into one cycle ?
Primary functions of a CPU
Fetch, read/decode, ALU, memory, write
RISC
Reduced Instruction Set Computer Many line of code 1 line of assembly = 1 clock cycle machine oriented breaking down complex instructions into a lot of small, simple operations software good for smaller devices such as mobile devices easy to pipeline
CISC
Complex Instruction Set Computer 1 instruction = several clock cycles more complex instructions less code hard to pipeline programmer oriented
Static and Dynamic RAM (differences)
Static: faster, expensive
Dynamic: slower, cheaper
ROM
Read-only memory
non-volatile
usually contains information about the starting or booting up the computer
Data can’t be changed
RAM
Random Access Memory
Pretty Fast
temporarily access data
volatile (will lose memory if power is off)
If the CPU has enough RAM memory it won’t have to access the hard drives and therefore it will be a lot faster.
TYPES OF RAM
DRAM (dynamic)
- constantly refreshed because uses capacitors
- stores data in memory cells (capacitors and transistors)
- computer’s main memory
SRAM
- CPU cache
- more expensive and faster than the DRAM
- no refresh circuit
Types of DRAM
1) Synchronous DRAM (SDRAM)
- runs at the same speed as the CPU
- more instructions can be performed
2) Double Data Rate SDRAM
- double the bandwidth - 2x data rate, without altering the frequency
- double pumping method
- DDR4
Memory Types
RAM NVRAM (non-volatile): flash, SSDs ROM PROM (programmed once by the user) EPROM (can be erased electronicaly) EEPROM (can be erased and rewritten) FLASH: EEPROM but smaller, faster and has more storage
DRAM packages
SIMM (old, 32-bit)
DIMM (Double In-line Memory Module)
the wider the bus, the more data can pass through it
BUSES
control, address and data bus
transfer data through wires
parameters: width, speed, throughput
Control bus
Contains information such as what the operations if (read, write), enable and other ‘control’ stuff
Address bus
Used by the CPU to tell the memory what the address for the data is
Data bus
Data is transferred through that bus
width of the address bus
how many addresses can be accessed -
if the width is f.e. 32-bits then 2^n locations can be accessed
width of the data bus
How much data can be transferred at once
usually the same as the machine
bus speed
number of transfers per second
bus cycle: single transfer over the bus
data throughput (efficiency)
width * width
Addressing the I/O devices
Separate address space and Mapped
Separate address space
Separate address space for the I/O with different machine code
Mapped I/O
Share the address space with the memory but have specific address locations (contained in the control bus)
Same machine code - simpler
Storage Devices
Internal (HDDs) and External (USB, optical)
