SilverStone 350W Gold Flex ATX Alternatives: 6 Similar Picks Compared
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The silverstone technology fx350 g vt flex atx alternatives list helps you find compatible power supplies for compact builds. This original unit delivers 350W of continuous power with 80 Plus Gold efficiency in a small Flex ATX form factor. It features fixed cables and a single +12V rail, making it ideal for steady, low-power systems. You might look for other options if you need more wattage, a different form factor, or modular cabling for better cable management.
This guide compares 6 similar picks based on overlapping specifications. The selection includes other Flex ATX units like the SilverStone 500W and Ptcliss 600W for users needing higher density in the same small chassis. It also lists standard ATX alternatives such as the MSI MAG 850W and Corsair RM850x Shift for standard desktop cases where size is not a constraint. Each option is evaluated by its published specs, including efficiency ratings, modularity, and connector types. You can choose based on whether you prioritize compact size, higher wattage, or modern PCIe support. This approach ensures you find a unit that matches your specific hardware requirements without guesswork.
Our top pick: SilverStone 350W Gold Flex ATX PSU.
How each alternative compares
SilverStone 500W Flex ATX Power Supply
The SilverStone FX500-G offers 500W of continuous power, which is 150W more than the original 350W unit. It maintains the same 80 Plus Gold efficiency rating and Flex ATX form factor, ensuring similar power density in a nearly identical physical footprint. The dimensions are 3.21 by 1.59 by 5.91 inches, compared to the original’s 3.3 by 1.6 by 6 inches. It also uses fixed cables like the base model. You should choose this if you need more headroom for slightly more powerful components without changing your case size. It keeps the compact profile while raising the wattage ceiling for small form factor builds.
Ptcliss 600W Fully Modular Flex ATX PSU
The Ptcliss FLEX-600W provides 600W of power, significantly higher than the original 350W. It shares the 80 Plus Gold efficiency and Flex ATX form factor. The key difference is modularity; this unit is fully modular, whereas the original has fixed cables. This allows you to connect only the cables you need, potentially improving airflow in tight spaces. The dimensions are 3.2 by 1.58 by 6.5 inches, making it slightly longer but lighter at 1.55 pounds. Pick this if you prioritize cable management and higher wattage over the fixed-cable simplicity of the SilverStone FX350-G-VT.
FSP FlexGURU 500W Flex ATX PSU
The FSP FlexGURU Pro delivers 500W of power, exceeding the original 350W output. It matches the 80 Plus Gold efficiency and Flex ATX form factor. Its physical dimensions are 1.59 by 3.21 by 5.91 inches, which swaps the width and height orientation compared to the original. It weighs 2.18 pounds, making it lighter than the 3-pound original. Like the base model, it uses fixed cables. Choose this unit if your chassis requires a specific orientation for the power supply or if you need more power density in a compact 1U server or SFF build without sacrificing efficiency.
MSI MAG 850W Fully Modular ATX Power Supply
The MSI MAG A850GL is a standard ATX unit, not Flex ATX. It offers 850W of power, which is far more than the 350W original. It features fully modular cables and supports PCIe 5.1 with a 12V-2x6 connector. The dimensions are 8.75 by 4.92 by 12 inches, making it much larger and incompatible with compact Flex ATX cases. It includes a 10-year warranty. Select this only if you are building a standard desktop gaming PC and do not need the small form factor. It provides massive power and modern connectivity but lacks the compact size required for 1U applications.
Corsair RM850x Shift 850W White ATX Power Supply
The Corsair RM850x Shift is a standard ATX power supply, not Flex ATX. It provides 850W of power, significantly higher than the 350W original. It shares the 80 Plus Gold efficiency rating but uses fully modular cables. It supports PCIe 5.1 and ATX 3.1 standards. The dimensions are 5.91 by 3.39 by 6.3 inches, which is much larger than the compact Flex ATX form factor. It weighs 3.75 pounds. This unit is suitable for standard ATX cases needing modern PCIe support. It is not a viable alternative for compact builds that require the small footprint of the SilverStone FX350-G-VT.
Corsair RM1000x Shift 1000W Power Supply
The Corsair RM1000x Shift is a standard ATX unit, not Flex ATX. It delivers 1000W of power, which is much higher than the 350W original. It maintains 80 Plus Gold efficiency and uses fully modular cables. It supports ATX 3.0 standards. The dimensions are 5.91 by 5.08 by 7.09 inches, making it significantly larger than the compact Flex ATX form factor. It weighs 4.2 pounds. This power supply is designed for standard ATX cases requiring high wattage for high-end components. It cannot be used in compact builds that require the small dimensions of the original SilverStone unit.
Quick picks
Our 7 picks
SilverStone 350W Gold Flex ATX PSU
Best for: compact, efficient low-power systems
- Wattage
- 350W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fixed Cables
- PCIe Connector Type
- PCIe 6pin
- Form Factor
- Flex ATX
- Dimensions
- 6 × 3.3 × 1.6 inches
View on Amazon: SilverStone 350W Gold Flex ATX PSU Affiliate link
This Silverstone unit delivers 350W of continuous power in a compact Flex ATX form factor. It features 80 Plus Gold efficiency and fixed cables for a clean build. The single +12V rail supports PCIe 6-pin connectors. It is rated for 24/7 operation at 40℃. This power supply suits users who need reliable, efficient power for small form factor systems without the complexity of modular wiring.
Pros
- 80 Plus Gold efficiency rating
- 350W continuous output at 40℃
- Class-leading single +12V rail
- Supports PCIe 6-pin connectors
Cons
- Fixed cables limit cable management flexibility
- 350W output is lower than many alternatives
- Single PCIe 6-pin connector restricts high-power GPU support
Good fit if
- You need a compact Flex ATX power supply
- You prioritize high efficiency over maximum wattage
- You are building a low-power 1U or small form factor system
Skip if
- You require modular cables for cleaner builds
- You need more than 350W of power
- You plan to use high-power PCIe 8-pin GPUs
Verdict: Silverstone FX350-G-VT 350W Flex ATX provides efficient, steady power for small builds. It fits users who value compact size and gold efficiency over high wattage or modular flexibility.
SilverStone 500W Flex ATX Power Supply
Best for: Compact systems needing reliable 500W Gold efficiency
- Wattage
- 500W
- Efficiency Rating
- 80 PLUS Gold
- Form Factor
- Flex ATX
- Dimensions
- 5.91 × 3.21 × 1.59 inches
- Weight
- 2.87 pounds
View on Amazon: SilverStone 500W Flex ATX Power Supply Affiliate link
The Silverstone FX500-G is a 500W Flex ATX power supply with 80 PLUS Gold efficiency. It features a single +12V rail and Japanese primary capacitors for stable 24/7 operation. At 2.87 pounds, it fits standard Flex ATX slots. This unit suits users needing reliable high-density power for compact systems or servers where space is limited but efficiency matters.
Pros
- 500W continuous output rated for 40°C
- 80 PLUS Gold efficiency certification
- Single +12V rail design
- Japanese primary capacitors
Cons
- Lower wattage than 600W alternatives on this list
- Non-modular cable management
- Heavier than some compact competitors
Good fit if
- You need a reliable 500W source for a Flex ATX chassis
- You prioritize 80 PLUS Gold efficiency in a small form factor
- You require a single +12V rail for stable component power
Skip if
- You need more than 500W of continuous power
- You prefer fully modular cables for cleaner builds
- You require a higher wattage unit like 850W
Verdict: Silverstone FX500-G 500W Flex ATX delivers solid Gold efficiency in a compact 500W package, making it a strong choice for users who need reliable power density without the bulk of higher-wattage units.
Ptcliss 600W Fully Modular Flex ATX PSU
Best for: High-wattage Flex ATX builds
- Wattage
- 600W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 8-pin, 6-pin
- Form Factor
- Flex ATX
- Dimensions
- 6.5 × 3.2 × 1.58 inches
View on Amazon: Ptcliss 600W Fully Modular Flex ATX PSU Affiliate link
This Ptcliss unit delivers 600W of power in a compact Flex ATX form factor. It carries an 80 Plus Gold efficiency rating, meaning it operates at high energy savings. The design is fully modular, allowing you to connect only the cables you need. It includes multiple protection circuits to safeguard your components. This supply suits users needing reliable power for small form factor builds.
Pros
- 600W output capacity
- 80 Plus Gold efficiency rating
- Fully modular cable design
- Multiple built-in protection circuits
Cons
- Third-party brand with limited market presence
- Heavier build at 1.55 pounds
- Non-standard PCIe connector mix (2x8-pin, 2x6-pin)
Good fit if
- You need more than 350W in a Flex ATX chassis
- You require high efficiency for energy-sensitive environments
- You want a fully modular cable setup
Skip if
- You need standard 8-pin PCIe connectors for modern GPUs
- You prefer established brands like Silverstone or Corsair
- You require a lighter power supply for tight spaces
Verdict: Ptcliss 600W Flex ATX Gold PSU offers high wattage and efficiency for small builds. It fits users needing robust power in a compact form factor who can adapt to its specific connector layout.
FSP FlexGURU 500W Flex ATX PSU
Best for: Compact 1U servers and SFF builds
- Wattage
- 500W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Non-Modular
- Fan Size
- 40mm
- Warranty
- 5-Year
- Form Factor
- Flex ATX
View on Amazon: FSP FlexGURU 500W Flex ATX PSU Affiliate link
The FSP FlexGURU Pro is a 500W Flex ATX power supply with 80 Plus Gold efficiency. It uses a 40mm fan and Japanese capacitors for stable output. The unit measures 5.91 by 3.21 by 1.59 inches. It includes safety protections and round black cables. This unit suits small form factor builds, 1U servers, and edge computing tasks where space and reliability matter.
Pros
- 500W output capacity
- 80 Plus Gold efficiency rating
- 40mm fan with intelligent speed control
- Japanese main capacitors for reliability
- Includes universal mounting bracket
Cons
- 40mm fan size is smaller than standard ATX fans
- Non-modular fixed cabling limits cable management
- Heavier at 2.18 pounds than some competitors
Good fit if
- You need 500W in a Flex ATX form factor
- You are building a 1U server or SFF PC
- You require 80 Plus Gold efficiency
Skip if
- You need a modular power supply
- You require standard 120mm fan cooling
- You need more than 500W of power
Verdict: FSP FlexGURU Pro 500W Flex ATX delivers reliable power for compact builds. It fits users who need 500W in a small chassis with high efficiency.
MSI MAG 850W Fully Modular ATX Power Supply
Best for: Standard desktop gaming PCs
- 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 an 850W ATX 3.1 power supply designed for gaming. It features 80 Plus Gold efficiency and a fully modular design. The unit supports PCIe 5.1 with a 12V-2x6 connector. It measures 12 by 8.75 by 4.92 inches. This model includes a 10-year warranty for long-term reliability.
Pros
- 850W output capacity
- 80 Plus Gold efficiency
- ATX 3.1 and PCIe 5.1 support
- Fully modular cabling
- 10-year warranty
Cons
- ATX form factor is larger than Flex ATX options
- 12-inch length may not fit small cases
- Not compatible with 1U server chassis
Good fit if
- You need high wattage for modern gaming GPUs
- You prefer fully modular cables for clean builds
- You want a long warranty period
Skip if
- You are building a 1U server
- You require a Flex ATX form factor
- You have a small form factor case with limited PSU depth
Verdict: MSI MAG A850GL 850W ATX is a high-wattage ATX unit that fits standard desktop gaming builds but lacks the compact size needed for 1U server applications.
Corsair RM850x Shift 850W White ATX Power Supply
Best for: Standard ATX cases needing PCIe 5.1
- 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 Affiliate link
The Corsair RM850x Shift is a fully modular ATX power supply rated at 850 watts. It features 80 Plus Gold efficiency and supports ATX 3.1 and PCIe 5.1 standards. This unit is designed for modern high-end builds. Its white finish and compact dimensions suit specific chassis requirements. It provides stable power for demanding components.
Pros
- 850W output capacity
- Fully modular cable design
- 80 Plus Gold efficiency rating
- ATX 3.1 and PCIe 5.1 support
Cons
- ATX form factor does not fit Flex ATX cases
- White color may not match dark builds
- Larger physical dimensions than 1U alternatives
Good fit if
- You need an ATX PSU for a standard case
- You require PCIe 5.1 compatibility for new GPUs
- You prefer a white aesthetic for your build
Skip if
- You are building a 1U or Flex ATX server
- You need a compact 1U form factor
- You are upgrading an older ATX 2.x system
Verdict: Corsair RM850x Shift 850W ATX suits users needing modern PCIe 5.1 support in a standard ATX case. It is not suitable for compact 1U Flex ATX builds.
Corsair RM1000x Shift 1000W Power Supply
Best for: standard ATX cases needing high wattage
- Wattage
- 1000W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fully Modular
- ATX Version
- ATX 3.0
- Dimensions
- 7.09 × 5.91 × 5.08 inches
- Weight
- 4.2 pounds
View on Amazon: Corsair RM1000x Shift 1000W Power Supply Affiliate link
This Corsair unit delivers 1000W of power in a standard ATX form factor. It is fully modular and certified 80 Plus Gold. The ATX 3.0 compliance ensures support for modern PCIe 5.0 graphics cards. It measures 7.09 by 5.91 by 5.08 inches and weighs 4.2 pounds. You should choose this if you need high wattage in a standard case size.
Pros
- 1000W output capacity
- Fully modular cable design
- ATX 3.0 and PCIe 5.0 compliant
- 80 Plus Gold efficiency rating
Cons
- Standard ATX form factor is bulkier than Flex ATX options
- Heavier at 4.2 pounds compared to compact alternatives
- Larger dimensions limit fit in small form factor cases
Good fit if
- You need high wattage for powerful graphics cards
- You have a standard ATX case with room for size
- You want ATX 3.0 native support for new GPUs
Skip if
- You are building in a 1U or small form factor chassis
- You require a Flex ATX power supply for tight spaces
- You need a compact unit under 6 inches in length
Verdict: Corsair RM1000x Shift 1000W ATX 3.0 suits users with standard ATX cases who need substantial power for high-end components. It is not suitable for compact builds requiring Flex ATX dimensions.
Specifications side by side
| Spec | SilverStone 350W Gold Flex ATX PSU | SilverStone 500W Flex ATX Power Supply | Ptcliss 600W Fully Modular Flex ATX PSU | FSP FlexGURU 500W Flex ATX PSU | MSI MAG 850W Fully Modular ATX Power Supply | Corsair RM850x Shift 850W White ATX Power Supply | Corsair RM1000x Shift 1000W Power Supply |
|---|---|---|---|---|---|---|---|
| Wattage | 350W | 500W | 600W | 500W | 850W | 850W | 1000W |
| Efficiency Rating | 80 Plus Gold | 80 PLUS Gold | 80 Plus Gold | 80 Plus Gold | 80+ Gold | 80 Plus Gold | 80 Plus Gold |
| Modularity | Fixed Cables | not stated | Fully Modular | Non-Modular | Fully Modular | Fully Modular | Fully Modular |
| ATX Version | not stated | not stated | not stated | not stated | ATX 3.1 | ATX 3.1 | ATX 3.0 |
| PCIe Connector Type | PCIe 6pin | not stated | 8-pin, 6-pin | not stated | 12V-2x6 | PCIe 5.1 | not stated |
| Fan Size | not stated | not stated | not stated | 40mm | not stated | not stated | not stated |
| Warranty | not stated | not stated | not stated | 5-Year | 10 Year | not stated | not stated |
| Form Factor | Flex ATX | Flex ATX | Flex ATX | Flex ATX | Compact | ATX | ATX |
| PCIe Version | not stated | not stated | not stated | not stated | PCIe 5.1 | PCIe 5.1 | not stated |
| Recommended Use | not stated | not stated | not stated | not stated | Gaming | not stated | not stated |
| Connector | not stated | not stated | not stated | not stated | 12V-2x6 Connector | not stated | not stated |
| Size | not stated | 500W | not stated | 500W | 850W (PCIE 5) | 850W | 1000W |
| Device Compatibility | not stated | not stated | not stated | NAS, PCs | not stated | not stated | not stated |
| Dimensions | 6 × 3.3 × 1.6 inches | 5.91 × 3.21 × 1.59 inches | 6.5 × 3.2 × 1.58 inches | 5.91 × 1.59 × 3.21 inches | 12 × 8.75 × 4.92 inches | 6.3 × 5.91 × 3.39 inches | 7.09 × 5.91 × 5.08 inches |
| Weight | 3 pounds | 2.87 pounds | 1.55 pounds | 2.18 pounds | not stated | 3.75 pounds | 4.2 pounds |
| Model | SST-FX350-G-VT | not stated | FLEX-600W | FLEX GURU 500-T | not stated | not stated | not stated |
| Color | not stated | not stated | not stated | Black | not stated | White | Black |
If your chassis supports larger power supplies, you can review silverstone tek micro atx alternatives for comparable specifications.
Frequently asked questions
Is the SilverStone FX350-G-VT the best option for small builds?
Yes, it is ranked as the best overall choice for compact, efficient low-power systems. It provides 350W of steady power in a small Flex ATX form factor. The unit measures 3.3 inches wide and weighs 3 pounds. You get 80 Plus Gold efficiency, which suits users who value compact size over high wattage.
What is the most affordable Flex ATX power supply on this list?
The SilverStone 500W Flex ATX is the best budget pick. It delivers 500W of continuous power with 80 Plus Gold efficiency. Its dimensions are 3.21 inches wide and 1.59 inches high. This unit offers reliable power density in a compact package, making it a strong choice for users needing more wattage than the 350W model.
Which Flex ATX PSU offers the highest wattage?
The Ptcliss 600W Fully Modular Flex ATX PSU is the highest wattage option in this category. It provides 600W of power in a compact form factor. The unit measures 3.2 inches wide and 1.58 inches high. It is fully modular, which helps manage cable clutter in small builds that need robust power output.
Is there a premium Flex ATX option for 1U servers?
The FSP FlexGURU 500W Flex ATX PSU is the best premium choice for compact 1U servers. It delivers 500W of reliable power with 80 Plus Gold efficiency. The unit is very thin at 1.59 inches high and 3.21 inches wide. It fits users who need substantial power in a small chassis with high efficiency.
Can I use an ATX power supply in a Flex ATX case?
No, standard ATX power supplies do not fit Flex ATX cases. Units like the MSI MAG 850W and Corsair RM850x Shift are standard ATX form factors. They measure over 8 inches wide and nearly 5 inches high. These are designed for standard desktop gaming PCs and lack the compact size needed for 1U server applications or small form factor builds.
Which power supply supports the latest PCIe 5.1 standard?
The Corsair RM850x Shift 850W supports PCIe 5.1 and ATX 3.1 standards. It is a standard ATX unit, not a Flex ATX option. The white unit measures 5.91 inches wide and 3.39 inches high. It is suitable for standard ATX cases needing modern PCIe support but is not suitable for compact Flex ATX builds.
What is the highest wattage standard ATX option available?
The Corsair RM1000x Shift 1000W is the highest wattage standard ATX option. It supports ATX 3.0 and delivers 1000W of power. The black unit measures 5.91 inches wide and 5.08 inches high. It suits users with standard ATX cases needing substantial power for high-end components, but it is not suitable for compact builds requiring Flex ATX dimensions.