Best SilverStone PC Power Supplies Under $150: 2 Spec-Based Picks
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Finding a reliable SilverStone PC power supply under $150 requires looking at the hard numbers. This guide compares 2 models based strictly on the specifications published on their listings. The top pick is the SilverStone 500W Flex ATX Power Supply. It leads because its 80 Plus Gold efficiency rating ensures stable output in a tight space. You need to decide if your build fits a Flex ATX or TFX form factor. This guide helps you choose the right unit for your specific case size and power needs.
Quick picks
| # | Product | Best for | Price |
|---|---|---|---|
| 1 | SilverStone 500W Flex ATX Power Supply Best overall | Compact high-efficiency builds | Check price of SilverStone 500W Flex ATX Power Supply on Amazon |
| 2 | SilverStone 400W TFX Power Supply Best budget | Compact TFX builds needing efficiency | Check price of SilverStone 400W TFX Power Supply on Amazon |
The best fit for you
- You need the most compact model on the list SilverStone 500W Flex ATX Power Supply Its Flex ATX form factor measures just 1.59 inches in height.
- You want a standard TFX unit with high efficiency SilverStone 400W TFX Power Supply It offers 80 Plus Gold efficiency in a standard TFX size.
- You prioritize low noise and high standards in tight spaces SilverStone 400W TFX Power Supply The TX400x Gold TFX is designed for low noise operation.
Our 2 picks
SilverStone 500W Flex ATX Power Supply
Best for: Compact high-efficiency builds
- 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. The unit supports 24/7 operation at 40°C. Its compact dimensions measure 5.91 x 3.21 x 1.59 inches. This makes it suitable for small form factor builds requiring reliable power in a small footprint.
Pros
- 80 PLUS Gold efficiency rating
- 500W continuous output at 40°C
- Single +12V rail design
- Japanese primary capacitors
Cons
- Limited to Flex ATX form factor
- Only 500W capacity available
- No multi-rail flexibility
Good fit if
- You need a compact Flex ATX PSU
- You want high efficiency in a small size
- You require 24/7 reliability
Skip if
- You need standard ATX form factor
- You require more than 500W
- You want multi-rail +12V options
Verdict: SilverStone FX500-G 500W Flex ATX fits small builds needing efficient power. It delivers stable output in a tight space. Choose it for compact systems requiring reliability.
SilverStone 400W TFX Power Supply
Best for: Compact TFX builds needing efficiency
- Wattage
- 400W
- Efficiency Rating
- 80 PLUS Gold
- PCIe Connector Type
- 6+2pin
- Fan Size
- 80mm
- Form Factor
- TFX
- Dimensions
- 6.9 × 3.4 × 2.6 inches
View on Amazon: SilverStone 400W TFX Power Supply Affiliate link
This SilverStone unit is a 400W TFX power supply with 80 PLUS Gold efficiency. It measures 3.4 by 2.6 by 6.9 inches and uses an 80mm fan. The design supports 24/7 operation at 40°C and runs quietly at 18 dBA. You should choose this if you need a compact, high-efficiency source for a small form factor build that requires reliable continuous power.
Pros
- 80 PLUS Gold efficiency rating
- 400W continuous output at 40°C
- Quiet 80mm fan at 18 dBA
- Standard TFX form factor
Cons
- Limited to single PCIe 6+2pin connector
- Lower wattage than Flex ATX competitors
- Smaller physical footprint limits cable routing
Good fit if
- You need a TFX form factor
- You want high efficiency in a small case
- You require silent operation under load
Skip if
- You need more than 400W of power
- You require multiple PCIe connectors
- You are building a standard ATX desktop
Verdict: SilverStone TX400x Gold TFX delivers compact efficiency for small builds. It fits users who prioritize low noise and high standards in tight spaces.
Specifications side by side
| Spec | SilverStone 500W Flex ATX Power Supply | SilverStone 400W TFX Power Supply |
|---|---|---|
| Wattage | 500W | 400W |
| Efficiency Rating | 80 PLUS Gold | 80 PLUS Gold |
| PCIe Connector Type | not stated | 6+2pin |
| Fan Size | not stated | 80mm |
| Form Factor | Flex ATX | TFX |
| Size | 500W | 400W |
| Dimensions | 5.91 × 3.21 × 1.59 inches | 6.9 × 3.4 × 2.6 inches |
| Weight | 2.87 pounds | not stated |
| Color | not stated | black (lead-free paint) |
| Model | not stated | SST-TX400-G |
Check Efficiency And Physical Dimensions
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Verify Efficiency Certifications
Look for the 80 Plus Gold rating on your chosen unit. This spec indicates that the power supply converts at least 87% of AC power to DC output at typical loads. Higher efficiency reduces wasted energy as heat. Both products in this guide hold this certification. This means less strain on your cooling system and lower electricity consumption over time. Verify the label matches the listing to ensure you are getting the certified model. This spec is critical for sustained performance in compact cases where heat dissipation is limited.
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Match Width To Case
Measure the width of your chassis power supply bay carefully. The Flex ATX option measures 3.21 inches wide, which is narrower than standard ATX units. The TFX model is 3.4 inches wide. You must ensure your case can accommodate these specific widths. A mismatch prevents installation entirely. Check the manufacturer specifications for your computer case before purchasing. Do not assume all small form factor units fit the same space. Precise width measurement is the first step in ensuring physical compatibility with your build.
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Check Height Constraints
Height is often the limiting factor in small form factor builds. The Flex ATX unit has a height of 1.59 inches. This allows it to fit in extremely tight spaces where taller units would block other components. The TFX model stands at 2.6 inches high. You need to verify the clear height in your case. Components like graphics cards or drive cages may interfere if the height is insufficient. Compare your case specifications against these numbers to avoid clearance issues during assembly.
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Confirm Length Fitment
The length of the power supply must not obstruct other components. The Flex ATX unit is 5.91 inches long. The TFX model extends to 6.9 inches. You should check the distance from the mounting bracket to any nearby drives or cables. Exceeding the available length can prevent the case from closing properly. It may also crowd other hardware, restricting airflow. Measure the internal depth of your power supply compartment to ensure both units fit without modification.
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Assess Weight Limits
Consider the weight if your mounting bracket has strict load limits. The Flex ATX unit weighs 2.87 pounds. While light, this mass still rests on the mounting screws. Ensure your case brackets can support this weight without sagging. Heavier units may require additional support in some chassis designs. Although these are compact units, proper support ensures long-term reliability. Check the mounting hardware specifications for your case to confirm it can handle the unit's mass safely over time.
Frequently asked questions
Is the SilverStone 500W Flex ATX good for small cases?
Yes, it is designed specifically for compact builds. The unit measures 3.21 inches wide, 1.59 inches high, and 5.91 inches long. Its Flex ATX form factor fits tight spaces where standard units will not. It delivers stable output while maintaining an 80 Plus Gold efficiency rating.
What is the difference between Flex ATX and TFX power supplies?
Flex ATX units are generally smaller and thinner than TFX models. The top Flex ATX option here is only 1.59 inches high. The TFX alternative is slightly larger at 2.6 inches high. Both form factors allow for efficient power delivery in compact chassis, but physical dimensions vary.
Does the SilverStone 400W TFX have a high efficiency rating?
Yes, it carries an 80 Plus Gold certification. This rating means the power supply converts at least 87% of AC power to DC output at typical loads. It helps reduce wasted energy as heat. The unit is available in black with lead-free paint for a clean look.
How heavy is the SilverStone 500W Flex ATX unit?
The unit weighs 2.87 pounds. This weight accounts for its internal components and casing materials. It is a compact unit with dimensions of 3.21 by 1.59 by 5.91 inches. The weight is typical for a high-efficiency power supply in this size class.
Can I use the SilverStone 400W TFX in a standard mini-ITX case?
Yes, if your case supports the TFX form factor. The unit measures 3.4 inches wide, 2.6 inches high, and 6.9 inches long. It delivers 400W of power with 80 Plus Gold efficiency. Ensure your case has the specific mounting holes and clearance for a TFX unit.
Which SilverStone PSU is best for low noise builds?
The SilverStone 400W TFX is noted for low noise performance. It is designed for users who prioritize quiet operation in tight spaces. The 80 Plus Gold efficiency also contributes to lower heat generation, which can reduce fan speed. It is a solid choice for silent compact systems.