CPU

The CPU is often called the “brain of the computer.” It executes instructions from software, processes data, and coordinates tasks across all other components.

Core Functions

• Instruction Execution: Reads and processes commands from programs.
• Arithmetic & Logic: Performs calculations and logical comparisons.
• Control Unit: Directs data flow between memory, storage, and peripherals.
• Registers & Cache: Provides ultra‑fast temporary storage for active tasks.

Key Specifications

• Clock Speed (GHz): Determines how many cycles per second the CPU can execute.
• Cores & Threads: Multiple cores allow parallel processing; threads improve multitasking.
• Cache Levels (L1, L2, L3): On‑chip memory that speeds up data access.
• Instruction Set Architecture (ISA): Defines how software communicates with hardware (e.g., x86, ARM).

Major Players (2025)

• Intel: Core Ultra processors with integrated AI acceleration.
• AMD: Ryzen and EPYC CPUs, strong in gaming and servers.
• Apple: M‑series chips (ARM‑based), optimized for macOS ecosystem.
• Qualcomm: Snapdragon processors for mobile and AI PCs.
• Huawei: Kirin chips for smartphones, focusing on AI and 5G.

Architecture essentials by brand

Intel

• Core design: Performance (P) cores + Efficiency (E) cores, large L3, advanced branch prediction.
• Key features: AVX‑512 variants (on Xeon), AVX2, Intel Thread Director, integrated NPU on Core Ultra.
• Packaging: EMIB, Foveros 3D stacking in select products.
• Models to know:
  • Core Ultra 7/9 (mobile AI PC), Core i9‑14900K (desktop),
  • Xeon Scalable (Sapphire Rapids) for HPC/AI, Xeon 6 for efficiency at scale.

AMD

• Core design: Zen 4/Zen 5 with wide front‑end, large ROB, robust cache; SMT for 2 threads per core.
• Key features: AVX‑512 on Zen 4, Ryzen AI NPUs, strong memory controllers (DDR5), PCIe Gen5.
• Packaging: Chiplet architecture (CCD + IOD), 3D V‑Cache on X3D parts.
• Models to know:
  • Ryzen 7 7800X3D (gaming), Ryzen 9 7950X/8950X (desktop),
  • Threadripper 7970X/7995WX (HEDT/workstation),
  • EPYC 9004 Genoa/Bergamo (server density and HPC).

Apple

• Core design: High IPC performance cores + efficiency cores; unified memory architecture (UMA).
• Key features: Powerful GPU blocks, Neural Engine, media engines; tight hardware–software integration.
• Models to know: M3/M3 Pro/M3 Max (TSMC N3), M4 (latest iPad, higher efficiency and AI).

Qualcomm

• Core design: Oryon custom ARM cores (X Elite), big‑little configurations on mobile.
• Key features: On‑die NPUs, advanced ISP, integrated 5G; strong AI PC push.
• Models to know: Snapdragon X Elite/X Plus (Windows on ARM laptops), Snapdragon 8 Gen 3/4 (flagship phones).

MediaTek

• Core design: All‑big core strategy on Dimensity 9300; advanced GPU and AI cores.
• Key features: Efficient AI accelerators, fast modem, competitive graphics.
• Models to know: Dimensity 9300/9300+, next‑gen 9400.

Samsung

• Core design: ARM Cortex X/Prime/Efficiency cores; AMD GPU collaboration on mobile.
• Key features: Integrated NPUs, advanced camera pipelines.
• Models to know: Exynos 2400/2500.

Huawei

• Core design: ARM‑compatible cores with in‑house design; emphasis on power efficiency.
• Key features: Integrated 5G (regional variations), NPUs for on‑device AI.
• Models to know: Kirin 9000S/9010.

RISC‑V ecosystem

• Core design: Modular ISA with extensible vectors; customizable cores for domain‑specific needs.
• Use cases: IoT, edge AI, microcontrollers, accelerators; growing interest in Linux‑capable cores.

Instruction sets and extensions

• x86‑64 (Intel/AMD): Mature ecosystem; AVX/AVX2/AVX‑512, AES‑NI, SHA, virtualization (VT‑x/AMD‑V).
• ARMv8/ARMv9: NEON, SVE/SVE2 (vectors), crypto extensions; TrustZone for secure execution.
• RISC‑V: RV64/32 base with modular extensions; RVV (vector), Zk (crypto), hypervisor extensions.

Process nodes and manufacturing

• TSMC: N7→N5→N4→N3/N3E; leading density and efficiency used by AMD, Apple, Qualcomm, MediaTek.
• Intel: Intel 7, Intel 4; roadmap to 20A/18A with RibbonFET (GAAFET) and PowerVia.
• Samsung Foundry: 5 nm/4 nm EUV; pushing 3 nm GAA.
• SMIC: ~7 nm class advancements; domestic ecosystem support.

Packaging and memory

• Chiplets: AMD CCD/IOD; improves scalability and yields.
• 3D stacking: Intel Foveros; AMD 3D V‑Cache for gaming/HPC.
• HBM integration: Primarily on GPUs/accelerators; appearing on CPU‑adjacent AI chips.
• Interconnects: PCIe Gen4/Gen5/Gen6, CXL for coherent memory expansion on servers.

How to choose a cpu (by use case)

• Gaming desktop:
  • AMD Ryzen 7 7800X3D or Ryzen 9 X3D for cache‑sensitive titles.
  • Intel Core i7/i9 14th Gen for high clocks and mixed workloads.
• AI PC/mobile productivity:
  • Intel Core Ultra or AMD Ryzen AI with NPUs;
  • Snapdragon X Elite if you prioritize battery life and on‑device AI on Windows on ARM.
• Workstation/HEDT:
  • Threadripper PRO 79xx WX or Intel Xeon W for multi‑core rendering, CAD, and simulation.
• Servers:
  • EPYC 9004 (Bergamo/Genoa) for density and memory bandwidth;
  • Xeon Scalable for ecosystem features and accelerators.