GAMEMAX SFX Power Supply 850W Alternatives: 6 Similar Picks Compared

Latest update: October 20, 2026

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You are looking at gamemax sfx power supply 850w alternatives because the GAMEMAX unit offers specific specs that may not fit every build. This unit provides 850W of power in a compact SFX form factor. It carries an 80 Plus Gold efficiency rating and supports ATX 3.0 standards. The inclusion of a 12VHPWR connector allows it to handle high-end graphics cards directly. Full modularity helps manage cable clutter in small cases. Japanese capacitors aim to ensure stable performance under load.

You might want something else if your case requires a standard ATX size instead of SFX. Some builders prefer different efficiency ratings or longer warranty periods. Others may need PCIe 5.1 support rather than the ATX 3.0 standard found here. The list includes 6 similar picks compared to the original. These alternatives were chosen because their specifications overlap with the GAMEMAX unit. You will find options with different form factors, connector types, and brand reputations. This guide helps you find the right power supply for your specific case and component requirements.

Our top pick: GAMEMAX 850W SFX Gold Power Supply.

How these alternatives compare

Corsair RM850x Shift 850W White ATX Power Supply

The Corsair RM850x Shift uses the standard ATX form factor, so it will not fit in small cases designed for SFX units. It shares the 80 Plus Gold efficiency and 850W output, but it supports the newer ATX 3.1 standard and PCIe 5.1. This makes it better for modern graphics cards requiring the updated 12VHPWR connector. You should choose this if you have a standard tower case and need the latest power delivery standards. The larger size allows for different internal layouts, but it sacrifices the compact footprint that defines the GAMEMAX SFX option.

EVGA SuperNOVA 850 GM SFX Power Supply

The EVGA SuperNOVA 850 GM matches the GAMEMAX in form factor, wattage, and efficiency rating, making it a direct size alternative. It also features full modularity and an 80 Plus Gold certification. The key difference is the warranty coverage, which extends to ten years. This longer term provides added security for long-term builds. You might prefer this unit if you value extended manufacturer support over the specific component choices in the GAMEMAX. It maintains the same compact dimensions, ensuring it fits in the same small chassis while offering a different brand ecosystem and protection plan.

MSI MPG 850W Gold ATX 3.1 Power Supply

The MSI MPG 850W Gold is an ATX unit, so it lacks the compact SFX size required for mini-ITX builds. It matches the 850W output and 80 Plus Gold efficiency, but it supports ATX 3.1 and PCIe 5.1 with a 12V-2x6 connector. This makes it suitable for standard gaming towers with modern GPUs. You should pick this if you do not need a small form factor. It offers a ten-year warranty and is designed for larger cases where space is less constrained. The larger physical size does not impact performance but removes the ability to use it in compact SFX-compatible cases.

GAMEMAX GS Series 650W SFX PSU

The GAMEMAX GS 650W SFX keeps the same compact form factor and 80 Plus Gold efficiency rating as the 850W model. It is fully modular, just like the original. The main difference is the reduced wattage output of 650W. This lower power level is sufficient for mid-range graphics cards but may limit high-end builds. You should choose this if your components require less power and you want to save space or cost. It maintains the same physical dimensions, ensuring compatibility with the same small cases, but it provides less headroom for power-hungry hardware compared to the 850W variant.

ASRock Steel Legend White 850W ATX 3.1 PSU

The ASRock Steel Legend White 850W is an ATX unit, meaning it cannot fit in SFX-sized cases. It matches the 850W output and 80 Plus Gold efficiency, while supporting ATX 3.1 and featuring a 12V-2x6 connector. This makes it ideal for standard ATX towers needing modern GPU support. You should select this if you are building in a larger case and want a white finish. It offers superior efficiency ratings and a long warranty. The trade-off is the loss of compactness, as the larger ATX dimensions prevent it from being used in small form factor builds that require SFX power supplies.

ASRock PG-850G 850W PSU

The ASRock PG-850G 850W PSU is an ATX form factor unit, so it is not suitable for compact SFX cases. It provides 850W of power with 80 Plus Gold efficiency and supports ATX 3.1 and PCIe 5.1. It includes a 12V-2x6 connector for modern graphics cards. You should choose this for standard gaming towers where space allows for larger power supplies. It prioritizes modern connector support and reliability over size. The larger physical footprint means it will not fit in mini-ITX chassis, but it offers robust performance for standard builds that do not require the specific dimensions of an SFX power supply.

Quick picks

#	Product	Best for	Price
1	GAMEMAX 850W SFX Gold Power Supply Best overall	compact high-wattage builds	Check price of GAMEMAX 850W SFX Gold Power Supply on Amazon
2	Corsair RM850x Shift 850W White ATX Power Supply Best budget	Standard ATX builds needing PCIe 5.1 support	Check price of Corsair RM850x Shift 850W White ATX Power Supply on Amazon
3	EVGA SuperNOVA 850 GM SFX Power Supply Best premium	compact high-wattage builds	Check price of EVGA SuperNOVA 850 GM SFX Power Supply on Amazon
4	MSI MPG 850W Gold ATX 3.1 Power Supply Also great	Standard ATX gaming builds with PCIe 5.1 GPUs	Check price of MSI MPG 850W Gold ATX 3.1 Power Supply on Amazon
5	GAMEMAX GS Series 650W SFX PSU Also great	small form factor builds needing Gold efficiency	Check price of GAMEMAX GS Series 650W SFX PSU on Amazon
6	ASRock Steel Legend White 850W ATX 3.1 PSU Also great	Standard ATX cases needing high efficiency	Check price of ASRock Steel Legend White 850W ATX 3.1 PSU on Amazon
7	ASRock PG-850G 850W PSU Also great	Standard ATX cases needing PCIe 5.1 support	Check price of ASRock PG-850G 850W PSU on Amazon

Our 7 picks

Best overall

GAMEMAX 850W SFX Gold Power Supply

Best for: compact high-wattage builds

Wattage: 850W
Efficiency Rating: 80 Plus Gold
Modularity: Full Modular
ATX Version: ATX 3.0
PCIe Connector Type: 12VHPWR
Form Factor: SFX

View on Amazon: GAMEMAX 850W SFX Gold Power Supply

This is a fully modular SFX power supply rated at 850W. It carries an 80 Plus Gold efficiency certification and supports ATX 3.0 standards. The unit includes a native 12VHPWR connector for modern graphics cards. You get Japanese capacitors and a quiet fan for stable operation. It is designed for compact builds that need high power density.

Pros

80 Plus Gold efficiency rating
Full modular cable design
Includes 12VHPWR PCIe 5.0 connector
ATX 3.0 compatible
SFX form factor for small cases

Cons

SFX size limits airflow compared to ATX units
No app or software control mentioned
Brand reputation is less established than major competitors

Good fit if

You are building in a small form factor case
You need a high wattage in a compact size
You want a fully modular setup with modern connectors

Skip if

You require an ATX standard size for better airflow
You prefer a brand with a longer track record
You need software monitoring capabilities

Verdict: GAMEMAX SFX 850W Gold PSU fits users who need maximum power in a tiny chassis. It delivers the necessary specs for high-end GPUs in compact builds.

Best budget

Corsair RM850x Shift 850W White ATX Power Supply

Best for: Standard ATX builds needing PCIe 5.1 support

Wattage: 850W
Efficiency Rating: 80 Plus Gold
Modularity: Fully Modular
ATX Version: ATX 3.1
PCIe Connector Type: PCIe 5.1
Dimensions: 6.3 × 5.91 × 3.39 inches

View on Amazon: Corsair RM850x Shift 850W White ATX Power Supply

This is a fully modular ATX power supply rated at 850W with 80 Plus Gold efficiency. It supports ATX 3.1 and PCIe 5.1 standards for modern graphics cards. The unit measures 6.3 inches in length and weighs 3.75 pounds. It features a zero RPM fan mode for silent operation at low loads. You should consider this unit if you need a reliable white ATX power supply with full modularity.

Pros

850W output capacity
Fully modular cable design
80 Plus Gold efficiency rating
Supports ATX 3.1 standard
Includes PCIe 5.1 connector

Cons

ATX form factor is larger than SFX units
6.3-inch length may not fit small cases
White color may not match dark builds

Good fit if

You are building a standard ATX mid-tower or full-tower case
You need PCIe 5.1 support for next-gen GPUs
You prefer a white power supply for visible builds

Skip if

You are building a compact ITX or SFX case
You need a smaller power supply like 650W
You require a black power supply for stealth builds

Verdict: Corsair RM850x Shift 850W ATX is a robust choice for standard ATX cases requiring PCIe 5.1 support. It suits users who prioritize efficiency and modularity in a white finish.

Best premium