ASUS ROG Loki SFX-L 850W Platinum - Compact High-Output PSU

Our review of the ASUS ROG Loki SFX-L 850W Platinum finds it aimed squarely at small-form-factor gamers and builders who need high, reliable power in a compact package. The single biggest reason to buy is its combination of ATX 3.0 compatibility and a bundled 16-pin PCIe cable that supports modern PCIe Gen 5 graphics, delivering up to 600W to a GPU while keeping noise and temperatures low thanks to the 120mm Axial-tech fan and proprietary ROG heatsinks. This unit balances efficiency, cooling, and build quality for demanding SFF builds.

Key Features

• ATX 3.0 compatible: Supports modern power delivery standards and includes a 16-pin PCIe cable to supply up to 600W to PCIe Gen 5 graphics cards for future-proofed builds.
• 80 PLUS Platinum efficiency: Operates up to 92% efficiency to reduce waste heat, improve stability under load, and lower overall system noise.
• Axial-tech 120mm PWM ARGB fan: Delivers controlled airflow with PWM control to keep thermals in check while maintaining quiet operation.
• ROG heatsinks: Cover critical components to lower temperatures, which can extend component lifespan and reduce audible fan activity.
• Lambda A Certification: Certified for low noise under 25 dB, making it a good fit for noise-sensitive systems.
• Fully modular cabling: Lets builders use only the cables they need for cleaner SFF layouts and easier routing.

Who It's For

The ASUS ROG Loki SFX-L 850W Platinum is best for small-form-factor PC builders and gamers who want a compact power supply that can handle high-end GPUs and modern power standards while staying quiet. Its combination of ATX 3.0 compatibility and a bundled 16-pin PCIe cable makes it particularly suitable for users planning PCIe Gen 5 graphics or heavy GPU draws.

It may be less compelling for casual desktop users who never push GPU or CPU power limits or for those on strict budgets, since the Platinum efficiency and SFX-L form factor target performance and compact builds rather than the lowest possible price.

Pros & Cons

Pros

• High efficiency and low heat with 80 PLUS Platinum performance for sustained loads.
• Quiet operation backed by Lambda A certification and a 120mm PWM fan that keeps noise below 25 dB in many scenarios.
• Compact SFX-L design with fully modular cabling and a bundled 16-pin PCIe cable for PCIe 5.0 GPUs.
• ROG-grade cooling and heatsinks that help extend component longevity under heavy use.

Cons

• Some customer reports show mixed functionality and variable cable quality, indicating occasional unit or cable issues though many owners report excellent reliability.
• Higher upfront cost compared with basic ATX units, reflecting its efficiency and SFX-L engineering.

Specifications

Form factor	SFX-L
Wattage	850W
Efficiency rating	80 PLUS Platinum (up to 92% efficient)
Fan	120mm Axial-tech PWM ARGB fan
Compatibility	ATX 3.0 compatible, PCIe Gen 5 ready
Certification	Lambda A certified (low noise)
Warranty	10 year warranty

Our Verdict

The ASUS ROG Loki SFX-L 850W Platinum is a compelling choice for SFF builders who need strong, modern power delivery in a small package and are willing to pay for efficiency, silence, and future-ready GPU support. It offers excellent build quality and cooling, and although some buyers report mixed experiences with cables or individual units, the overall package and 10 year warranty make it a good value for serious compact gaming systems.

Frequently Asked Questions

Does this PSU support modern PCIe 5.0 graphics cards?
Yes. It includes a bundled 16-pin PCIe cable and is ATX 3.0 compatible to supply up to 600W to PCIe Gen 5 GPUs.

How loud is the power supply under load?
The unit is Lambda A certified for low noise and uses a 120mm PWM fan, keeping noise typically below 25 dB in many operating conditions.

Is this suitable for a high-end small-form-factor gaming PC?
Yes. Its 850W output, high efficiency, modular cabling, and ROG cooling features make it well suited for high-performance SFF builds.