4 Hardware Flashcards
Semiconductor
Material whose electrical properties are intermediate between a good conductor of electricity and nonconductor of electricity
Megabyte Giga Tera Peta Exa
1 million bytes 1 billion bytes 1 trillion bytes 1 quadrillion bytes 1 quintillion bytes
Ascii
Binary code most widely used on cmoputers in Eng and WEuro langs
Unicode
2 bytes for every character, rather than 1
Multicore processor
Divides work over more than one processor
CPU
Control unit
Logic unit
Machine cycle
CPU:
Fetches instruction
Decodes
Executes
Stores it
DRAM
Must be constantly refreshed by CPU or will lose its contents
SDRAM
Synchronous dynamic RAM
DDR-SDRAM
Double-data synchronous dynamic RAM
DDR2 and DDR3
RDRAM
Rambus DRAM, faster than SDRAM
SRAM
Static RAM
Doesn’t need refresh
MRAM
Newer Nagnetoresistive RAM Uses magnetic charge Faster Stores more data than RAM Retains contents when power off
Cache
Level 1: part of the microprocessor chip 8 to 128 kb Faster than level 2 Level 2: not part of processor chip External cache 64kb to 16 mb Most commonly cited Level 3: on motherboard 2-8 mb
VRAM
Hard disk
Extends RAM
Flash memory
No battery
Can be erased and programmed more than once
Used in PCs for BIOS Instructions
CMOS
Powered by battery
Time, date, calendar
Frontside bus
Connects CPU within itself and to main memory
Expansion bus
Bus that connects CPU with expansion slots on motherboard and peripherals
RAID
Redundant array of indep desks
Links drives within single cabinet or multiple cabinets, sends data to the computer along several parallel paths simultaneously
Same data stored in several places
CDs
Pits are 0 bits
Smooths are 1 bit
CD-R recording only once
CD-RW rewriting many times
DVD+R and DVD-R write once
DVD-RW, DVD-RAM, DVD+RW, rewritable
Zones:
NA - 1 Europe + ME -2 Asia -3 SA and Aus -4 Africa, Russia - 5
Solid state drives
Flash or SDRAM
