Msi or ASUS? PC Power Supplies Compared in 2026
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This guide covers the msi vs ASUS PC power supply debate. You are comparing the MSI MAG 850W and the ASUS ROG Thor 1200W. Both units share a 10-year warranty and support modern ATX standards. The main difference lies in their power output and efficiency. The MSI offers 850W with Gold efficiency, while the ASUS provides 1200W with Platinum efficiency. Your choice depends on your system's power needs and case size.
Key differences
| Aspect | MSI MAG 850W Fully Modular ATX Power Supply | ASUS ROG Thor 1200W Platinum II |
|---|---|---|
| Wattage | 850W | 1200W |
| Efficiency Rating | 80+ Gold | 80+ Platinum |
| ATX Version | ATX 3.1 | not listed |
| Modularity | Fully Modular | not listed |
| Form Factor | ATX | not listed |
Which one should you choose?
Choose MSI MAG 850W Fully Modular ATX Power Supply if
- You need a compact, fully modular unit for standard gaming builds.
- You require PCIe 5.1 compatibility with a 12V-2x6 connector.
- You want a proven ATX 3.1 design with a Gold efficiency rating.
Choose ASUS ROG Thor 1200W Platinum II if
- You have a high-end system requiring up to 1200W of power.
- You prioritize maximum efficiency with an 80+ Platinum certification.
- You prefer a smaller physical footprint with a 135mm fan for quiet operation.
Verdict: Choose the MSI MAG if you need a versatile, fully modular power supply for most gaming PCs. Pick the ASUS ROG Thor if your build demands higher wattage and peak efficiency. Both options offer reliable 10-year warranties for long-term use.
MSI vs ASUS PSU Comparison
Efficiency Rating
The ASUS ROG Thor 1200W Platinum II holds a clear advantage in electrical efficiency. It carries an 80 Plus Platinum certification, meaning it converts more AC power to DC with less waste heat. The MSI MAG A850GL PCIE5 is rated 80 Plus Gold. While Gold is excellent for most builds, Platinum is a higher tier. This matters if you run your system hard or want to reduce electricity costs over time. The ASUS unit leads here by one certification level. Both are highly efficient, but the Thor is the more efficient choice for power savings.
Wattage Output
Power output is the biggest difference between these two units. The ASUS ROG Thor provides 1200W of continuous power. The MSI MAG offers 850W. If you are building a high-end gaming rig with a top-tier GPU and CPU, the ASUS unit provides more headroom. The MSI unit is sufficient for mid-range to high-end builds. You need to match the wattage to your components. The ASUS wins for raw power potential, while the MSI is adequate for many users. Choose based on your specific component list.
ATX Version
The MSI MAG A850GL supports the newer ATX 3.1 standard. The ASUS ROG Thor 1200W Platinum II does not list a specific ATX version in its provided data. ATX 3.1 ensures compatibility with the latest motherboard power requirements and signaling. This is a spec advantage for the MSI unit if you are using the very latest platform. The ASUS unit may still be compatible, but the explicit support for ATX 3.1 is only confirmed for the MSI. This gives the MSI a slight edge in future-proofing for motherboard standards.
PCIe Version
The MSI MAG A850GL is listed as PCIe 5.1 ready with a 12V-2x6 connector. This is the new standard for modern high-end graphics cards. The ASUS ROG Thor 1200W Platinum II does not list its PCIe version or connector type in the provided data. If you are buying a new GPU that requires the 12V-2x6 connector, the MSI unit is explicitly ready. The ASUS unit might support it, but the data does not confirm this. The MSI wins for confirmed modern GPU compatibility.
Physical Size
The ASUS ROG Thor 1200W is significantly smaller than the MSI MAG A850GL. The ASUS measures 5.9 inches wide and 3.3 inches high. The MSI is 8.75 inches wide and 4.92 inches high. The ASUS unit is also much shorter at 7.4 inches long versus 12 inches for the MSI. This compact form factor makes the ASUS easier to fit in smaller cases. The MSI is a standard ATX size. If case space is tight, the ASUS is the better choice for fitment.
Which PSU matches your build needs
Users with high-end GPUs needing PCIe 5.1
This MSI unit supports ATX 3.1 and PCIe 5.1 standards. It includes a native 12V-2x6 connector for modern graphics cards. The fully modular design helps you manage cables easily. If your system requires the latest power delivery specifications, this choice fits your hardware requirements perfectly.
Builders prioritizing maximum efficiency and low heat
The ASUS model holds an 80 Plus Platinum certification. This rating means it wastes less energy as heat compared to lower tiers. Higher efficiency reduces electricity costs over time. The 135mm fan supports quiet operation with its 0dB mode. Choose this if you want top-tier electrical performance and thermal management.
Owners of standard mid-range gaming PCs
The 850W output from this MSI power supply is sufficient for most gaming rigs. It carries an 80 Plus Gold rating, which balances performance and cost. The compact dimensions help it fit in smaller cases. You get a solid 10-year warranty with this reliable unit for everyday gaming tasks.
The products compared
MSI MAG 850W Fully Modular ATX Power Supply
Best for: Standard ATX gaming builds
- Wattage
- 850W
- Efficiency Rating
- 80+ Gold
- Modularity
- Fully Modular
- ATX Version
- ATX 3.1
- PCIe Connector Type
- 12V-2x6
- Warranty
- 10 Year
View on Amazon: MSI MAG 850W Fully Modular ATX Power Supply Affiliate link
The MSI MAG A850GL is a fully modular 850W power supply built for modern gaming PCs. It carries an 80 Plus Gold efficiency rating and supports ATX 3.1 and PCIe 5.1 standards. The unit includes a native 12V-2x6 connector for next-gen graphics cards. With a 10-year warranty, it offers long-term reliability. Its compact dimensions help fit into smaller cases while delivering stable power for high-end components.
Pros
- 80 Plus Gold efficiency rating
- 10-year warranty coverage
- Native 12V-2x6 PCIe connector
- ATX 3.1 and PCIe 5.1 ready
- Fully modular cable design
Cons
- 80 Plus Gold rating is lower than Platinum competitors
- 850W output is less than 1200W options
- Dimensions are bulkier than standard SFX units
Good fit if
- You need a reliable 850W unit for a mid-to-high end build
- You want a 12V-2x6 connector for newer GPUs
- You prefer a fully modular design for clean cable management
Skip if
- You require 80 Plus Platinum efficiency for maximum savings
- You need more than 850W for extreme overclocking
- You are building in a case with strict size limits
Verdict: MSI MAG A850GL 850W Gold PSU suits gamers who want modern PCIe 5.1 support and a solid 10-year warranty without paying for higher efficiency tiers. It is a practical choice for standard ATX cases.
ASUS ROG Thor 1200W Platinum II
Best for: High-wattage high-end gaming builds
- Wattage
- 1200W
- Efficiency Rating
- 80+ Platinum
- Fan Size
- 135mm
- Warranty
- 10 Year
- Dimensions
- 7.4 × 5.9 × 3.3 inches
- Weight
- 11 pounds
View on Amazon: ASUS ROG Thor 1200W Platinum II Affiliate link
The ASUS ROG Thor 1200W Platinum II delivers serious power for high-end builds. It carries an 80+ Platinum efficiency rating and Lambda A++ certification. A 135mm PWM fan supports 0dB mode for quiet operation. The unit measures 7.4 by 5.9 by 3.3 inches and weighs 11 pounds. It includes a 10-year warranty. This power supply suits users needing maximum wattage and premium efficiency standards.
Pros
- 1200W output capacity
- 80+ Platinum efficiency rating
- 10-year warranty coverage
- 135mm PWM fan with 0dB mode
Cons
- 11-pound weight adds significant mass
- No mention of OLED display panel
- No mention of app connectivity
Good fit if
- You need 1200W for extreme gaming rigs
- You prioritize high efficiency ratings
- You want a long warranty period
Skip if
- You prefer lightweight power supplies
- You need smart monitoring features
- You are building a low-power system
Verdict: ASUS ROG Thor 1200W Platinum PSU fits users who demand maximum wattage and top-tier efficiency for their high-end PC builds.
Specifications side by side
| Spec | MSI MAG 850W Fully Modular ATX Power Supply | ASUS ROG Thor 1200W Platinum II |
|---|---|---|
| Wattage | 850W | 1200W |
| Efficiency Rating | 80+ Gold | 80+ Platinum |
| Modularity | Fully Modular | not stated |
| ATX Version | ATX 3.1 | not stated |
| PCIe Connector Type | 12V-2x6 | not stated |
| Fan Size | not stated | 135mm |
| Warranty | 10 Year | 10 Year |
| Form Factor | Compact | not stated |
| PCIe Version | PCIe 5.1 | not stated |
| Recommended Use | Gaming | not stated |
| Connector | 12V-2x6 Connector | not stated |
| Dimensions | 12 × 8.75 × 4.92 inches | 7.4 × 5.9 × 3.3 inches |
| Weight | not stated | 11 pounds |
| Size | 850W (PCIE 5) | not stated |
| Color | not stated | BLACK |
Frequently asked questions
Is the MSI MAG 850W compatible with PCIe 5.1 graphics cards?
Yes, this unit supports PCIe 5.1 standards. It features a native 12V-2x6 connector designed for modern high-end GPUs. This allows you to connect the latest graphics cards directly without needing adapter cables. The ATX 3.1 version ensures broad compatibility with current motherboard specifications.
Does the ASUS ROG Thor 1200W Platinum II run cooler than standard units?
Its Platinum efficiency rating helps reduce waste heat. This certification means the PSU converts more AC power to DC with less energy loss. Lower energy loss typically translates to reduced heat generation during operation, which can improve overall system stability and component longevity.
Can I use the MSI MAG 850W in a standard ATX case?
Yes, it is designed for standard ATX cases. The dimensions are 8.75 inches wide, 4.92 inches high, and 12 inches long. This form factor fits most mid-tower and full-tower chassis. The fully modular design also helps you manage cables neatly within the case.
Which power supply offers higher wattage for extreme gaming builds?
The ASUS ROG Thor 1200W Platinum II offers higher wattage. It provides 1200W of power output, making it suitable for high-end builds with multiple components. The MSI MAG 850W provides 850W, which is sufficient for standard gaming rigs but lower in total capacity.
Is the ASUS ROG Thor 1200W heavy?
Yes, it weighs 11 pounds. This weight is typical for high-wattage Platinum-rated units due to larger internal components. The compact dimensions of 5.9 inches wide and 7.4 inches long help it fit in various cases despite the heavier build quality.
Does the MSI MAG 850W require all cables to be plugged in?
No, it is fully modular. You can connect only the cables you need for your specific build. This reduces cable clutter inside your case and improves airflow. Unused cables can be stored separately rather than being permanently attached to the power supply unit.