Whether you’re building a compact gaming PC or a sleek workstation, choosing the right SFX power supply (PSU) is crucial. SFX PSUs are smaller than standard ATX power supplies, making them perfect for small-form-factor (SFF) builds.
In this guide, we’ll cover:
- What an SFX supply is
- Key features to look for
- Top product recommendations
- A buying guide for beginners
- FAQs
What Is an SFX Power ?
An SFX (Small Form Factor) power supply is a compact PSU designed for mini-ITX and other small PC cases. Unlike standard ATX PSUs, SFX models are smaller (100mm x 125mm x 63.5mm) but still deliver reliable power for high-performance builds.
SFX vs. SFX-L: What’s the Difference?
- SFX: Standard small size (100mm depth)
- SFX-L: Slightly longer (130mm depth) for larger fans and better cooling
Key Features
1. Wattage
- 500W–600W: Good for mid-range builds (e.g., RTX 3060, Ryzen 5)
- 750W–850W: Ideal for high-end GPUs (e.g., RTX 4080, Ryzen 9)
2. Efficiency Rating (80 Plus Certification)
Higher efficiency means less heat and lower electricity bills:
- 80 Plus Bronze: Budget-friendly
- 80 Plus Gold: Best balance of price and performance
- 80 Plus Platinum/Titanium: Premium efficiency
3. Modularity
- Non-modular: Fixed cables (cheaper but harder to manage)
- Semi-modular: Essential cables fixed, extras detachable
- Fully modular: All cables detachable (best for cable management)
4. Cooling & Noise
- 92mm fan: Common in SFX PSUs (can be noisy under load)
- 120mm fan: Found in SFX-L models (quieter)
5. Warranty & Reliability
Look for brands offering 5–10 years warranty (Corsair, Seasonic, Cooler Master).
Best SFX Power Supplies in 2024
Here are our top picks for different needs:
1. Best Overall: Corsair SF750 (750W, 80 Plus Platinum)
✅ Pros:
- Ultra-reliable with Japanese capacitors
- Fully modular for easy cable management
- Whisper-quiet operation
❌ Cons: - Expensive
- No RGB (if that matters to you)
2. Best Budget Pick: Cooler Master V650 SFX (650W, 80 Plus Gold)
✅ Pros:
- Affordable for a Gold-rated PSU
- Semi-modular design
- Decent cooling
❌ Cons: - Fan can get loud under heavy load
3. Best for High-End Builds: SilverStone SX1000 (1000W, 80 Plus Platinum)
✅ Pros:
- Massive 1000W for extreme builds
- Fully modular
- High efficiency
❌ Cons: - Very expensive
- SFX-L size (may not fit all cases)
Buying Guide
1. Check Your Case Compatibility
- Measure your case’s PSU space before buying.
- Some cases support SFX-to-ATX adapters if needed.
2. Calculate Your Power Needs
Use a PSU calculator (like OuterVision) to estimate wattage based on your components.
3. Prioritize Efficiency & Reliability
- 80 Plus Gold or higher is ideal for gaming PCs.
- Stick with trusted brands (Corsair, Seasonic, EVGA).
4. Consider Future Upgrades
If you plan to upgrade your GPU later, buy a higher-wattage PSU now.
Personal Experience: My SFX Build
I recently built a mini-ITX PC using the Corsair SF750. Here’s what I learned:
- Cable management was easy thanks to the fully modular design.
- Zero noise issues—even under load, the fan stayed quiet.
- No overheating despite the compact case.
If you’re going small but powerful, a high-quality SFX PSU is a must!
FAQs
1. Can I use an SFX PSU in an ATX case?
Yes, with an SFX-to-ATX adapter bracket (often included).
2. Are SFX PSUs more expensive than ATX?
Yes, due to their compact design, they often cost more.
3. Do SFX PSUs run hotter?
They can, but high-quality models (like Corsair SF750) manage heat well.
4. Is 600W enough for an RTX 3070?
Yes, but 750W is safer for future upgrades.
Final Thoughts
An SFX power supply is essential for compact, high-performance PCs. Whether you’re building a gaming rig or a workstation, prioritize wattage, efficiency, and reliability.
Our top recommendation:
- Best overall: Corsair SF750
- Budget pick: Cooler Master V650 SFX
- High-wattage beast: SilverStone SX1000
Got questions? Drop them in the comments! Happy building! 🚀
3 thoughts on “The Best SFX Power Supply”