Cache memory is placed between which two units of a computer?
- A.The CPU and the main memory
- B.The main memory and the hard disk
- C.The keyboard and the CPU
- D.The CPU and the printer
Correct answer
Explanation
The correct answer is A, the CPU and the main memory. Cache is a small block of static RAM that keeps the instructions and data most recently used by the processor. Because it answers in a fraction of the time DRAM takes, it hides the gap between a fast processor and slower main memory; a request satisfied from it is a cache hit and one that is not is a cache miss.
Option B describes a disk buffer or disk cache, a different arrangement and not what the term cache memory means in this chapter. Option C is wrong because input from a keyboard is handled by a controller and a small buffer, not by the CPU cache. Option D is wrong for the same reason on the output side, where a printer has its own buffer and the operating system uses spooling. Remember the levels as well: L1 lies inside each core, L2 next, and a larger L3 is shared between cores.
Read the full article: Memory and Storage: RAM, ROM, Cache and Units
Practice Questions
View allWhich of the following is the fastest memory in a computer system?
- A.Cache memory
- B.Register
- C.Main memory
- D.Hard disk
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A register is built into the CPU itself and holds the word the arithmetic and logic unit is operating on at that instant, so it is read and written in a single clock cycle.
Read the full explanation →How many bits make one nibble?
- A.2 bits
- B.4 bits
- C.8 bits
- D.16 bits
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A nibble is half a byte, that is four binary digits, and it matters because one nibble is written as exactly one hexadecimal digit, from 0 to F. That is why memory addresses in hexadecimal are read four bits at a time.
Read the full explanation →Which type of memory has to be refreshed thousands of times per second to retain its contents?
- A.SRAM
- B.DRAM
- C.ROM
- D.Flash memory
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Dynamic RAM stores each bit as a charge on a very small capacitor, and that charge leaks away in a few milliseconds, so the memory controller has to read and rewrite every cell continuously.
Read the full explanation →The contents of an EPROM chip are erased by exposing it to
- A.An electrical signal
- B.Ultraviolet light
- C.A magnetic field
- D.Infrared radiation
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An Erasable Programmable Read Only Memory chip carries a small quartz window over the silicon; ultraviolet light shone through that window releases the trapped charge from every cell at once and returns the chip to its blank state, after which it can be programmed again.
Read the full explanation →One terabyte is equal to how many gigabytes?
- A.100 GB
- B.512 GB
- C.1,024 GB
- D.2,048 GB
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Every step in the ladder of storage units multiplies by 1,024, because 1,024 is 2 raised to the power 10 and memory is addressed in binary.
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