Clock Speed is measured in Hertz (Hz) and represents the number of FDE cycles a CPU can perform per second; for example, equals 3.5 billion cycles per second.
Number of Cores refers to the number of independent processing units within a single CPU, allowing multiple instructions to be processed simultaneously.
Cache Size impacts speed because a larger cache allows more data to be stored close to the CPU, minimizing the need to access the much slower system RAM.
| Feature | CPU | RAM |
|---|---|---|
| Function | Processes instructions and data | Stores data currently in use |
| Speed | Extremely fast (internal) | Slower than CPU registers/cache |
| Volatility | Volatile (registers cleared) | Volatile (cleared when power is lost) |
Control Unit vs. ALU: The CU acts as the 'manager' that directs traffic, while the ALU is the 'worker' that performs the actual computation.
Registers vs. Cache: Registers hold the immediate instruction or data being worked on, whereas Cache holds copies of data that are likely to be needed soon.
The 'More Cores' Trap: Always remember that doubling the number of cores does not necessarily double the performance, as some software cannot split tasks across multiple cores.
Units of Measurement: Ensure you can convert between MHz and GHz; remember that .
Register Roles: Be precise about which register does what; for instance, the Program Counter (PC) always holds the address of the next instruction, not the instruction itself.
Performance Justification: When asked why a CPU is faster, mention specific characteristics like higher clock speed or larger cache and explain how they reduce processing time.
