Overview
This lecture explains the difference between 32-bit and 64-bit systems, CPU architectures like x86 and ARM, and the concept of processor cores.
32-bit vs 64-bit Operating Systems
- 32-bit and 64-bit refer to how much data a CPU can process at once and its total addressable memory.
- A 32-bit processor can address up to 2^32 units, or 4 GB of memory.
- A 64-bit processor can address up to 2^64 units, or 17 billion GB of memory (theoretically).
- Actual memory accessible by a computer is often less than the maximum possible.
- 64-bit operating systems require 64-bit hardware drivers, and similarly for 32-bit systems.
- “x86” refers to 32-bit Intel-compatible processors, derived from the 8086 CPU.
- “x64” refers to 64-bit Intel-compatible processors.
Application Compatibility
- 32-bit operating systems cannot run 64-bit applications.
- 64-bit operating systems can usually run both 32-bit and 64-bit applications.
- On Windows, 32-bit apps are installed in "Program Files (x86)", while 64-bit apps go in "Program Files".
ARM Architecture
- ARM stands for Advanced RISC Machine, designed by the company ARM Limited.
- ARM processors are energy efficient, generate less heat, and are fast.
- ARM processors are used in 99% of modern mobile phones and are increasingly found in desktops and laptops.
- ARM licenses its chip design to other manufacturers.
Processor Cores
- CPUs often contain multiple processor cores within a single chip (e.g., 8-core, 16-core).
- Each core can process instructions independently and has its own dedicated cache memory.
- Multiple cores allow simultaneous instruction processing, increasing efficiency.
- A CPU die’s structure shows individual cores and their associated cache areas.
Key Terms & Definitions
- 32-bit — System architecture with 32 binary digits per operation; addresses up to 4 GB of memory.
- 64-bit — System architecture with 64 binary digits per operation; addresses up to 17 billion GB of memory.
- x86 — Intel 32-bit processor architecture.
- x64 — Intel 64-bit processor architecture.
- ARM — Advanced RISC Machine, an efficient CPU architecture widely used in mobile devices.
- Processor core — An individual processing unit within a CPU capable of executing instructions.
Action Items / Next Steps
- Check your own system information to identify its CPU architecture, operating system type, and number of processor cores.