Extended ATX vs ATX: Which Motherboard Size Is Better for Your PC?

Choosing the right motherboard size directly affects your PC’s performance and expandability. Extended ATX (E-ATX) and ATX are two mainstream options, each with distinct strengths. This optimized guide breaks down their core differences to help you decide.

Core Differences at a Glance

Feature	ATX	E-ATX
Size	12×9.6 inches (305×244mm)	12×13 inches (305×330mm)
Expansion Slots	4–7 slots (sufficient for most users)	8+ slots (ideal for multi-component setups)
Power Delivery	Basic to mid-range (mainstream use)	Advanced (supports overclocking/high-power components)
Price	Budget-friendly	Premium (30–50% higher than ATX)
Case Compatibility	Most standard PC cases	Requires E-ATX/XL-ATX specific cases
Best For	Mainstream gaming, home/office use	High-end workstations, multi-GPU setups

Key Details You Need to Know

Size & Physical Design

• ATX: The industry standard for over 25 years. Its compact size fits 90% of PC cases, making it the go-to for most builds.

• E-ATX: Larger by 3.4 inches in width, this form factor prioritizes extra space for components—critical for power-hungry setups.

Expansion Capabilities

E-ATX excels here: With 8+ expansion slots, it supports multi-GPU configurations (SLI/CrossFire), multiple high-speed storage drives, or specialized cards (e.g., 10Gbps network adapters).

ATX works for most users: 4–7 slots handle a single GPU, a few storage drives, and basic upgrades (e.g., a Wi-Fi card). Only power users will hit its limits.

Power & Performance

• E-ATX: Built with more power phases and robust cooling to handle overclocked CPUs, high-end GPUs, or workstation-grade hardware (e.g., for 3D rendering or video editing).

• ATX: Delivers stable power for mainstream tasks—gaming, office work, or light content creation. It’s not designed for extreme overclocking or multi-component setups.

Cost & Compatibility

• Price: E-ATX motherboards cost 30–50% more than ATX due to their advanced features. ATX offers the best value for casual users.

• Cases: E-ATX requires a large case explicitly marked as E-ATX compatible. ATX fits in almost all mid-tower and full-tower cases, offering far more flexibility.

Final Verdict

• Choose ATX if you need a balanced, budget-friendly build for gaming, home use, or light content creation.

• Choose E-ATX if you’re building a high-end workstation, multi-GPU gaming rig, or server—and you’re willing to invest in a larger case and higher costs.