Why Modern Servers Matter: Architecture, Types, and the X86 vs ARM Battle

1. What Is a Server?

A server, often called a "Server" in English, is a high‑performance computer that provides various services over a network. It acts as a node that stores and processes roughly 80% of network data, earning the nickname "the soul of the network." While functionally similar to a desktop PC, servers demand higher stability, security, and performance, leading to distinct CPU, chipset, memory, storage, and networking hardware.

2. Server Components

2.1 Logical Architecture

The logical architecture mirrors that of a regular computer but is optimized for high‑performance computing. Key elements include the CPU for computation and memory for data storage, with heightened requirements for reliability, scalability, and manageability.

2.2 Hardware

Typical hardware blocks are:

Processor (CPU) and chipset

System memory (RAM)

I/O devices such as RAID cards, network cards, and HBA cards

Storage drives

Chassis, including power supplies and fans

Cost breakdown for a standard server: CPU & chipset ≈ 50%, memory ≈ 15%, external storage ≈ 10%, remaining hardware ≈ 25%.

2.3 Firmware and Operating System

Key firmware components are BIOS/UEFI, BMC (Baseboard Management Controller), and CMOS. The BIOS initializes hardware and hands control to the OS; UEFI is its modern successor. BMC enables out‑of‑band management and firmware updates, while CMOS stores BIOS settings. The operating system (32‑bit or 64‑bit) manages hardware resources and schedules tasks.

3. Server Classification

3.1 By Form Factor

Tower Server : Stand‑alone chassis, low density, typically single‑processor, suitable for small offices and specific workloads.

Rack Server : 19‑inch width, height measured in “U” (1U = 1.75 in), common sizes 1U, 2U, 4U, 8U, used in data centers.

Blade Server : Multiple server blades share a common chassis and power/fan infrastructure, offering high density.

Cabinet Server : Integrated compute, networking, and storage in a single enclosure, optimized for large‑scale data centers.

3.2 By Instruction‑Set Architecture

CISC (X86) : Intel/AMD processors, dominant in the market, typically run Windows or Linux.

RISC : Includes IBM Power, SPARC, and ARM‑based Kunpeng processors.

EPIC : Intel Itanium and similar designs.

RISC and EPIC servers are collectively referred to as non‑X86 servers.

3.3 By Processor Count

Servers are categorized as single‑socket, dual‑socket, quad‑socket, or octa‑socket, with dual‑socket designs currently most common. Multi‑socket systems employ Symmetrical Multi‑Processing (SMP) to share memory and I/O across CPUs, dramatically boosting throughput.

4. The X86 vs ARM Debate

Market data shows X86 servers dominate globally, with 2019 shipments of 12.5 million units and $69.4 billion in sales, outpacing non‑X86 servers. In China, X86 demand is projected to grow at a 9.1% CAGR (2020‑2024) driven by “new‑infrastructure” policies.

Advantages of X86:

High performance, e.g., 2U systems can host up to 48 cores.

Mature ecosystem with broad software compatibility.

Advantages of ARM:

Lower power consumption due to reduced instruction set.

Higher core density per unit area (ARM core ≈ 1/7 the size of an X86 core, enabling 4× more cores in the same footprint).

Emerging high‑core‑count designs such as Huawei Kunpeng 920 (7 nm, up to 64 cores), Ampere Altra (80 cores), and Marvell Thunder X3 (96 cores).

With growing data‑center support for ARM and backing from major cloud providers (e.g., AWS, Huawei), ARM servers are expected to gain market share, offering cost‑effective, energy‑efficient compute for edge and AI workloads.