LIAN LI SX1200P 1200W 80 PLUS Platinum Power Supply

Full Product Description

1200W High-Capacity Power Delivery

The LIAN LI SX1200P is a 1200W power supply designed for high-performance desktop systems that require substantial and stable power delivery. As the highest-output model in the SX Platinum Series, it provides a 1200W maximum DC output and a full 1200W combined +12V output.

Key benefits:

• 1200W maximum DC output
• 1200W combined +12V output
• 100W combined +3.3V and +5V output
• Designed for high-performance systems
• Suitable for demanding CPU and GPU configurations

80 PLUS Platinum Efficiency

The SX1200P carries 80 PLUS Platinum certification, with LIAN LI also identifying the SX Platinum Series as PPLP Platinum certified. The manufacturer states that the series can achieve up to 94% conversion efficiency at 50% load.

Key benefits:

• 80 PLUS Platinum certification
• PPLP Platinum certification
• Up to 94% conversion efficiency at 50% load
• Reduced power conversion losses
• Lower heat generation

ATX 3.1 and PCIe 5.1 Support

The SX1200P is designed for modern hardware with ATX 3.1 and PCIe 5.1 compatibility. It incorporates a reinforced 12V-2×6 high-current copper-alloy terminal for compatible next-generation graphics cards.

The SX Platinum Series is also specified to handle power excursions up to 200% of rated output, helping accommodate demanding transient power requirements.

Key benefits:

• ATX 3.1 ready
• PCIe 5.1 support
• 12V-2×6 high-current connector
• Copper-alloy terminal
• Supports power excursions up to 200%

Fully Modular Cabling

The SX1200P features a fully modular DC output design, allowing users to connect only the cables required by their particular system. LIAN LI also provides braided-texture cables and cable combs with the SX Platinum Series.

Key benefits:

• Fully modular cable design
• Cleaner cable management
• Easier installation
• Flexible system configuration
• Braided-texture cables
• Cable combs included

The 24-pin, CPU, and 12V-2×6 GPU cables include cable combs, while SATA and 12V-2×6-to-dual-PCIe cables use flat ribbon sleeving.

Extensive GPU Power Connectivity

The 1200W model includes three PCIe 6+2 cables along with two additional 12V-2×6-to-dual PCIe 6+2-pin cables. This provides flexible connectivity for high-performance graphics configurations.

Key benefits:

• Three PCIe 6+2 cables
• Two 12V-2×6-to-dual PCIe 6+2 cables
• Up to five PCIe 6+2 connectors
• 12V-2×6 GPU connectivity
• Flexible graphics-card power configuration

120mm Fluid Dynamic Bearing Fan

The SX1200P uses a 120mm FDB fan with a maximum speed of 2000 RPM. The smart stop/start system allows the fan to stop when the PSU load is at or below 40%, helping provide quieter operation during lower-load workloads.

Key benefits:

• 120mm FDB fan
• Up to 2000 RPM
• Smart fan stop/start
• Fanless operation up to 40% load
• Reduced fan noise at lower loads
• Minimum 100,000-hour average fanless operating time under the manufacturer’s specified conditions

The fanless mode can also be enabled or disabled using the switch on the rear of the PSU.

100% Japanese 105°C Capacitors

LIAN LI specifies that the SX Platinum Series uses 100% Japanese Rubycon, Nippon Chemi-Con, or Nichicon capacitors, with the components rated for 105°C operation.

Key benefits:

• Japanese capacitors
• 105°C-rated components
• Stable voltage regulation
• Lower ripple
• Designed for long-term reliability
• Suitable for demanding operating conditions

Comprehensive Protection

The SX1200P incorporates multiple protection systems to help safeguard the power supply and connected components.

Protection Features

• OCP — Over Current Protection
• OVP — Over Voltage Protection
• OTP — Over Temperature Protection
• OPP — Over Power Protection
• SCP — Short Circuit Protection
• UVP — Under Voltage Protection
• NLP — No Load Protection
• SIP — Surge & Inrush Protection

These protection features are officially listed by LIAN LI for the SX Platinum Series.

Compact 140mm ATX Form Factor

Despite its 1200W capacity, the SX1200P measures only 150 × 86 × 140mm. Its 140mm length provides additional room for cable routing and helps improve compatibility with a broad range of PC cases.

Key benefits:

• 150mm width
• 86mm height
• 140mm depth
• Standard ATX form factor
• Easier installation
• Additional cable-routing space
• Suitable for compact and mainstream PC builds

Open-Mesh Front Panel

The SX Platinum Series uses a patterned open-mesh front panel designed to improve airflow through the PSU while maintaining its clean appearance.

Key benefits:

• Open-mesh front panel
• Improved airflow
• Supports PSU cooling
• Functional ventilation design
• Clean appearance

10-Year Manufacturer Warranty

LIAN LI backs the SX Platinum Series with a 10-year warranty, providing long-term coverage for the SX1200P.

Key benefits:

• 10-year warranty
• Long-term manufacturer coverage
• Designed for extended system use
• Suitable for premium PC configurations

Why Choose LIAN LI SX1200P?

• 1200W maximum power output
• 1200W combined +12V output
• 80 PLUS Platinum certification
• PPLP Platinum certification
• ATX 3.1 compatibility
• PCIe 5.1 support
• Reinforced 12V-2×6 high-current connector
• Up to 200% power-excursion support
• Fully modular cable design
• Braided-texture cables with cable combs
• 120mm FDB fan
• Fanless operation up to 40% load
• 100% Japanese 105°C capacitors
• Comprehensive protection system
• Compact 140mm ATX length
• 10-year warranty

Frequently Asked Questions

What is the wattage of the LIAN LI SX1200P?

The SX1200P has a 1200W maximum DC output with a 1200W combined +12V output.

Is the SX1200P an ATX 3.1 power supply?

Yes. LIAN LI specifies the SX1200P as ATX 3.1 compatible.

Does the SX1200P support PCIe 5.1?

Yes. The SX Platinum Series supports PCIe 5.1 and includes a reinforced 12V-2×6 high-current terminal.

Is the SX1200P fully modular?

Yes. The SX1200P uses a fully modular DC output cable design.

What type of fan does it use?

It uses a 120mm Fluid Dynamic Bearing fan with a maximum speed of 2000 RPM.

Does the fan stop at low loads?

Yes. The smart stop/start system enables fanless operation at loads up to 40%.

What capacitors are used?

LIAN LI specifies 100% Japanese Rubycon, Nippon Chemi-Con, or Nichicon 105°C-rated capacitors.

What protections are included?

The SX1200P includes OPP, NLP, OVP, SCP, OCP, OTP, SIP, and UVP.

What are the dimensions?

The SX1200P measures 150 × 86 × 140mm.

How long is the warranty?

The SX Platinum Series carries a 10-year warranty.

Upgrade Your Setup Today

The LIAN LI SX1200P combines 1200W of power with 80 PLUS Platinum efficiency, ATX 3.1, PCIe 5.1, 12V-2×6 connectivity, fully modular cabling, smart fan control, Japanese 105°C capacitors, and comprehensive protection. Its 140mm ATX length also provides useful flexibility when installing a high-capacity PSU in systems where internal space and cable routing matter. With a 10-year manufacturer warranty and features designed around modern high-performance hardware, the SX1200P provides a strong power foundation for demanding PC builds.