How to Choose a Reliable Power Supply for NAS with SATA Connectors

Selecting a Reliable Power Supply for NAS with Sufficient SATA Connectors

When choosing a reliable power supply for a NAS with enough SATA connectors, you should focus on power output of at least 600-750W, voltage stability across all lines (especially 3.3V, 5V and 12V), and quality of the cable system. It’s important to avoid overloading connectors and use quality extensions for SATA connections to prevent voltage drops that can lead to disk disconnections.

Contents

• Main Requirements for a NAS Power Supply
• Recommended Power and Technical Specifications
• Voltage Drop Issues and Solutions
• Selecting Specific Power Supply Models
• Safe SATA Expansion
• Optimal Cable Organization
• Installation and Setup Recommendations

Main Requirements for a NAS Power Supply

A reliable power supply for a file server must meet several key requirements that differ from a regular PC. First, voltage stability on all power lines is critically important, as hard drives are very sensitive to fluctuations. Studies show that even small drops can lead to drive disconnections [1].

Second, sufficient power - for NAS with multiple drives, a minimum of 650W is recommended, with 750-850W being better for power reserve [1, 3]. This is because when all disks start simultaneously, there is a peak load that significantly exceeds the nominal value.

Third, component quality - the power supply should have reliable capacitors and an efficient cooling system, as NAS operate in continuous 24/7 mode. Quality models from Seasonic, EVGA and other premium brands show stability even under prolonged load [1, 4].

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Recommended Power and Technical Specifications

For NAS with multiple hard drives, power should be selected based on the following parameters:

Power Requirements

• Minimum 650W for basic configuration of 8-12 drives
• 750-850W for systems with 12-20 drives or servers with high load
• 1000W+ for large NAS systems with 20+ drives [1, 3]

Voltage Characteristics

It’s critically important to pay attention to current on 3.3V and 5V lines, as these lines power the logical parts of the drives. 400-500W power supplies often have limited current (12-15A on each line), while more powerful models can provide up to 20A [2].

According to research, the standard SATA connector is rated for 3 x 5V/1.5A, but the 3.3V line often becomes a bottleneck, especially for 3.5" drives [6].

Efficiency Requirements

• Bronze (80+ Bronze) and higher efficiency level
• Semi-modular or modular design for better cable organization
• Overvoltage protection and short circuit protection [1, 4]

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Voltage Drop Issues and Solutions

Causes of Voltage Drops

In your case, the voltage drop issues down to 9V and 4V indicate serious problems with the power supply or cable system. The main causes of such problems are:

1. Insufficient power - the power supply is operating at the limit of its capabilities
2. Poor contact in connectors - especially relevant for Molex connectors that oxidize over time
3. Long or poor quality cables - cause significant voltage losses
4. Overloading individual lines - too many devices connected to one cable [5, 7]

Consequences of Voltage Drops

Voltage drops can lead to:

• Damage to drive electronics due to unstable power supply
• Data loss during sudden disconnections
• Reduced lifespan of storage devices
• Complete system failure [1, 8]

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Selecting Specific Power Supply Models

Based on research and user experience, several recommended models can be highlighted:

Premium Segment

• Seasonic PRIME TX-1000 - 1000W Titanium, excellent voltage stability
• be quiet! Dark Power 14 1000W - stable 12V voltage under full load [4]
• EVGA SuperNOVA 1000 P6 - reliable protection and stability

Mid-Range Segment

• Seasonic Focus GX-750 - 750W Gold, good price/quality ratio
• Corsair RM750x - 750W Gold, modular design
• be quiet! System Power 9 600W - 600W Bronze, but with good stability

Budget Options with Caution

Cheap power supplies should be avoided, even if they claim high power. They often have stability issues and limited capabilities for connecting drives [1, 2].

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Safe SATA Expansion

Expansion Problems

Your experience with problems with internal connectors and removable cables is a common issue. Main risks:

• Voltage drops when connecting too many devices to one cable
• Poor contact in connectors due to multiple connections/disconnections
• Overheating of connectors under high load [5, 7]

Recommended Solutions

1. Use dedicated Molex to SATA adapters

   • Each Molex connector can power up to 4 SATA devices
   • Use quality adapters with thick wires [8]

2. Individual cables for each drive

   • Connect each drive to a separate SATA connector on the PSU
   • Avoid “daisy-chain” connections [5]

3. Custom cables

   • You can order special SATA cables with different numbers of connectors
   • Use cables with wire gauge of at least 18AWG [7]

4. Separate power for drives

   • For critical systems, use separate power supplies
   • You can find PSUs with a large number of built-in SATA connectors [1]

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Optimal Cable Organization

Drive Connection Rules

1. No more than 4 drives per SATA cable

   • This is the standard limit for stable power supply
   • Exception - low-power drives (SSD) [5]

2. Load distribution across lines

   • Connect drives to different PSU SATA cables
   • Avoid overloading one power line [7]

3. Cable quality

   • Use original or certified cables
   • Thick wires (18AWG or less) for minimal loss [2]

Special Considerations for 3.5" Drives

For full-size hard drives, you may need to disable the 3.3V line (usually the orange wire), especially when using adapters [1]. Some drives may work unstably when 3.3V is supplied through adapters.

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Installation and Setup Recommendations

Power Supply Preparation

1. Check voltages before installation

   • Use a multimeter to check output voltages
   • Ensure all voltages are normal under load [1]

2. Cable organization

   • Use cable ties for neat routing
   • Avoid kinks and cable tension

3. Ventilation

   • Leave sufficient space for PSU cooling
   • Regularly clean dust from the system [4]

Monitoring and Maintenance

1. Install voltage monitoring

   • Use software to monitor voltages
   • Monitor stability under full load [1]

2. Regular inspection

   • Periodically check connector condition
   • Watch for signs of overheating or oxidation [8]

3. Backup

   • Always have current data backups
   • Periodically check data integrity [1]

Sources

1. r/HomeServer on Reddit: Advice For Power Supply With Lots of SATA Connectors
2. Linus Tech Tips: PSU for NAS
3. r/HomeServer: PSU for Ryzen based NAS/Server
4. Club386: be quiet! Dark Power 14 review
5. Linus Tech Tips: Power supply with the most sata connections
6. TrueNAS Community: PSU for 40 HDD solution
7. r/unRAID: PSU recommendations for 23+ SATA drives
8. r/DataHoarder: For those with more than 6-8 drives

Conclusion

When selecting a power supply for NAS with multiple SATA connectors, you should be guided by the following principles:

1. Priority of stability - choose models with proven voltage stability, even if they are more expensive. Voltage drops of 9V and 4V, as in your case, are unacceptable and require immediate power supply replacement.

2. Sufficient power - the calculated power should be 1.5-2 times the nominal system consumption to ensure reserve during peak loads.

3. Quality cable system - invest in good SATA cables and avoid cheap adapters that can cause power supply issues.

4. Proper load distribution - don’t overload individual power lines and use specialized solutions to expand the number of SATA connectors.

5. Regular monitoring - install a voltage control system and regularly check component condition to prevent data loss.

Following these recommendations, you can ensure reliable operation of your NAS server and avoid problems with drive disconnections due to unstable power supply.