Apevia 300W TFX Power Supply vs Apevia SFX 400W Power Supply (2026): Key Differences
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This guide compares the Apevia TFX AP300W 300W TFX Power Supply vs SFX AP400W Mini ITX Solution for compact builds. Both units provide essential power protections and use 80mm fans for cooling. The main difference lies in their physical dimensions and power output. The TFX model offers a standard 300W rating in a longer chassis, while the SFX variant delivers 400W in a more compact footprint. You need to check your case compatibility carefully before purchasing either unit.
Key differences
| Aspect | Apevia 300W TFX Power Supply | Apevia SFX 400W Power Supply |
|---|---|---|
| Wattage | 300W | 400W |
| Form Factor | TFX | SFX |
| Length | 6.75 inches | 5 inches |
| Width | 3.23 inches | 4 inches |
| +12V Rail Output | 20A | 28A |
Which one should you choose?
Choose Apevia 300W TFX Power Supply if
- You have a case designed specifically for TFX form factor power supplies.
- Your build requires a power supply with a length of 6.75 inches.
- You need a narrower unit with a width of 3.23 inches.
Choose Apevia SFX 400W Power Supply if
- You are building a compact system that supports SFX form factor.
- You need higher power output with a 400W rating.
- You want a shorter unit with a length of 5 inches.
Verdict: Choose the TFX model if your case strictly requires that specific form factor and length. Select the SFX model if you need more power and a shorter chassis width. Ensure your case supports the chosen form factor before proceeding.
TFX 300W vs SFX 400W Specs
Power Output
The Apevia SFX 400W Power Supply delivers more raw power than the Apevia 300W TFX Power Supply. The SFX model provides 400W total output, while the TFX unit is rated for 300W. This difference is driven by the 12V rail, which carries the most load for modern components. The SFX unit offers 28A on the +12V rail, compared to 20A on the TFX model. If your build requires higher wattage for a dedicated GPU or multiple drives, the SFX version has the advantage. The TFX unit is sufficient for lighter systems.
Form Factor
These two units use different physical standards, so they fit different cases. The Apevia 300W TFX Power Supply uses the TFX form factor, which is a standard size for small form factor builds. The Apevia SFX 400W Power Supply uses the SFX form factor. SFX units are generally wider than TFX units. The TFX model measures 6.75 inches in length, while the SFX model is shorter at 5 inches. You must check your case compatibility before buying. They are not interchangeable due to their distinct mounting hole patterns and dimensions.
Dimensions
Physical size matters for tight cases. The Apevia 300W TFX Power Supply has a length of 6.75 inches and a width of 3.23 inches. The Apevia SFX 400W Power Supply is shorter, measuring 5 inches in length, but it is wider at 4 inches. Both share the same height of 2.5 inches. The TFX unit is slightly heavier at 2.1 pounds, while the SFX unit weighs 2.03 pounds. If you have a case that limits width, the TFX model may fit better. If length is the constraint, the SFX model is the better choice.
Connectors
The Apevia SFX 400W Power Supply includes more detailed connector information in its specifications. It lists a 20+4pin main power connector, a 4pin 12V connector, a 6/8pin PCIe connector, two SATA connectors, two 4pin Molex connectors, and one 4pin Floppy connector. The Apevia 300W TFX Power Supply data does not list specific connector types. The SFX model explicitly mentions sleeved cables, which can help with cable management in small builds. You should verify that the TFX unit provides the necessary cables for your specific motherboard and peripherals.
Cooling
Both power supplies use an 80mm fan for forced air ventilation. The Apevia 300W TFX Power Supply uses a standard fan setup. The Apevia SFX 400W Power Supply features an automatically thermal sensing fan. This means the SFX fan speed adjusts based on internal temperature, potentially offering quieter operation under light loads. Both units rely on this single fan size for cooling efficiency. The thermal sensing feature in the SFX model provides a slight practical advantage for noise management in compact cases.
Choose the right PSU for your build
Users needing higher power for graphics cards
The Apevia SFX 400W Power Supply delivers 400W total output, which exceeds the 300W limit of the TFX model. It provides 28A on the +12V rail, allowing it to support more demanding components. The 6/8pin PCIe connector ensures compatibility with modern graphics cards that require dedicated power connections.
Owners of standard TFX cases
The Apevia 300W TFX Power Supply uses the TFX form factor, which fits specific chassis designs that do not accept SFX units. It measures 6.75 inches in length, providing a different footprint than the SFX alternative. This unit is the correct choice if your case strictly requires the TFX standard.
Builds requiring thermal sensing fan control
The Apevia SFX 400W Power Supply features an automatically thermal sensing fan. This allows the cooling to adjust based on internal temperatures, potentially improving efficiency during lighter loads. The TFX model uses forced air ventilation without this specific thermal sensing feature described in its specifications.
The products compared
Apevia 300W TFX Power Supply
Best for: compact TFX builds with low power needs
- Wattage
- 300W
- Fan Size
- 80mm
- Form Factor
- TFX
- Dimensions
- 6.75 × 3.23 × 2.5 inches
- Weight
- 2.1 pounds
View on Amazon: Apevia 300W TFX Power Supply Affiliate link
The Apevia TFX-AP300W is a 300W power supply designed for TFX form factor cases. It features an 80mm fan for forced air ventilation and supports 115-230V AC input. The unit provides specific rail outputs including +12V at 20A and maintains 5% tolerance on key voltages. This compact unit suits users building small form factor PCs who need a reliable, standard TFX solution.
Pros
- 300W total wattage output
- Standard TFX form factor
- 80mm cooling fan
- 5% voltage tolerance
Cons
- Lower 300W capacity compared to 400W alternatives
- Smaller 80mm fan may run louder under load
- Single 12V rail limits flexibility for high-end GPUs
Good fit if
- You are building a TFX-based mini PC
- You need a compact power supply for small cases
- You have modest power requirements under 300W
Skip if
- You require SFX form factor compatibility
- You need more than 300W of power
- You plan to use high-end graphics cards
Verdict: Apevia 300W TFX Power Supply fits small form factor builds with modest power needs, but you should skip it if you need higher wattage or SFX compatibility.
Apevia SFX 400W Power Supply
Best for: Compact Mini ITX and Micro ATX builds
- Wattage
- 400W
- PCIe Connector Type
- 6/8pin PCIe
- Fan Size
- 80mm
- Form Factor
- Mini ITX
- Dimensions
- 5 × 4 × 2.5 inches
- Weight
- 2.03 pounds
View on Amazon: Apevia SFX 400W Power Supply Affiliate link
This is a 400W SFX power supply designed for Mini ITX and Micro ATX builds. It features an 80mm thermal-sensing fan and fully sleeved cables. The unit provides 12V at 28A and includes essential connectors like a 6/8-pin PCIe, SATA, and Molex. Its compact 125x100x63.5mm size fits small cases. You should choose this if you need reliable power in a tight footprint.
Pros
- 400W output capacity for Mini ITX systems
- 80mm fan with automatic thermal sensing
- All cables are fully sleeved
- Includes 6/8-pin PCIe and SATA connectors
Cons
- Smaller 80mm fan may run louder under load
- Limited to 2 SATA and 2 Molex connectors
- Heavier at 2.03 pounds than typical SFX units
Good fit if
- You are building a compact Mini ITX PC
- You need a 400W power supply for small cases
- You prefer sleeved cables for a clean look
Skip if
- You require a larger 120mm fan for quieter operation
- You need more than 2 SATA connectors
- You are building a standard ATX mid-tower case
Verdict: Apevia 400W SFX Mini ITX PSU delivers solid power for small builds. It suits users who prioritize compact size and cable management over fan silence.
Specifications side by side
| Spec | Apevia 300W TFX Power Supply | Apevia SFX 400W Power Supply |
|---|---|---|
| Wattage | 300W | 400W |
| PCIe Connector Type | not stated | 6/8pin PCIe |
| Fan Size | 80mm | 80mm |
| Form Factor | TFX | Mini ITX |
| Dimensions | 6.75 × 3.23 × 2.5 inches | 5 × 4 × 2.5 inches |
| Weight | 2.1 pounds | 2.03 pounds |
| Size | TFX 300W | not stated |
| Color | Black | not stated |
| Model | TFX-AP300W | SFX-AP400W |
Frequently asked questions
Which power supply is better for a Mini ITX case?
The Apevia SFX 400W Power Supply is the better choice for Mini ITX builds. It follows the SFX form factor, which is the standard size for these compact cases. The TFX model uses a different physical layout that may not fit standard Mini ITX power supply bays without adapters or modification.
What are the physical dimensions of the Apevia TFX 300W?
The Apevia 300W TFX Power Supply measures 6.75 inches in length, 3.23 inches in width, and 2.5 inches in height. It weighs 2.1 pounds. These dimensions define its TFX form factor, requiring a case specifically designed to accommodate this longer, narrower shape compared to standard ATX or SFX units.
How much weight difference exists between the two units?
The Apevia SFX 400W Power Supply is slightly lighter than the TFX model. The SFX unit weighs 2.03 pounds, while the TFX version weighs 2.1 pounds. This minimal difference of less than an ounce does not significantly impact installation or case stability in small form factor builds.
Can I use the SFX PSU in a TFX case?
You likely cannot use the SFX unit in a standard TFX case without modification. The SFX power supply is shorter at 5 inches long compared to the TFX unit’s 6.75 inches. While they share the same height of 2.5 inches, the length difference means mounting holes and cable routing may not align correctly.
Which model offers more power for a graphics card?
The Apevia SFX 400W Power Supply offers more total power output. It provides 400W compared to the 300W limit of the TFX model. This higher wattage allows for more robust components or a slightly more powerful graphics card, assuming the case has adequate airflow for the 80mm fan used in both units.
Do both units use the same fan size?
Yes, both power supplies utilize an 80mm fan for cooling. This is standard for their respective form factors. The fan size helps maintain a compact profile while providing necessary airflow to dissipate heat generated by the internal components during operation.