The Lian Li SX Platinum SX1200P.W delivers 1200 watts of 80 PLUS Platinum efficiency in a compact 140mm ATX chassis, fully updated to ATX 3.1 and PCIe 5.1 standards to safely power high-end graphics cards. Finished in white with fully modular cabling, it provides a clean aesthetic and massive electrical headroom for demanding enthusiast builds.
Next-Generation ATX 3.1 and PCIe 5.1 Power
Built to handle the transient power spikes of modern flagship GPUs, the SX1200P.W complies with the strict ATX 3.1 specification. It features native PCIe 5.1 support, delivering power directly to compatible graphics cards through a single 12V-2x6 connector. This eliminates the need for bulky adapter cables and ensures a safer, more reliable connection under heavy sustained loads. With 1200W of total capacity, it easily accommodates high-core-count processors and heavily overclocked system configurations.
Platinum Efficiency in a Compact 140mm Footprint
High wattage often requires a longer chassis, but Lian Li has engineered the SX1200P.W into a standard 150 x 86 x 140 mm footprint. This shorter 140mm depth dramatically improves compatibility with smaller ATX cases and frees up valuable space in the lower chamber for cable routing. Internally, the unit achieves an 80 PLUS Platinum efficiency rating, meaning less power is drawn from the wall and less is wasted as heat. This electrical performance is driven by 100% Japanese 105°C capacitors, ensuring stable voltage regulation and long-term reliability.
Silent Operation Under Moderate Loads
Cooling is handled by a 120mm fluid dynamic bearing (FDB) fan that balances airflow with acoustics. The fan operates with a zero-RPM fanless mode up to 40% load. In practice, this means the power supply remains completely silent while the system draws 480W or less, making it ideal for desktop work, media consumption, and light gaming. When pushed to its absolute maximum, the fan spins up to 2000 RPM while maintaining a peak noise level of just 39.9 dBA.
Fully Modular Cabling for White Builds
The fully modular design allows you to connect only the cables your system actually requires, reducing case clutter and improving internal airflow. The power supply and its cables are colour-matched in white, making it a perfect foundation for bright, colour-coordinated builds. Alongside the primary motherboard and GPU cables, the unit provides extensive connectivity for complex storage and peripheral setups.
| Motherboard | 1x 24-pin |
| CPU | 2x EPS 4+4-pin |
| PCIe (Native) | 1x 12V-2x6 |
| PCIe (Standard) | 3x PCIe 6+2-pin |
| SATA | 8x SATA |
| Peripheral | 4x Molex |
Comprehensive Protection and 10-Year Warranty
A complete suite of electrical protections safeguards your expensive hardware against power anomalies. The SX1200P.W includes OCP (Over Current), OPP (Over Power), OVP (Over Voltage), UVP (Under Voltage), SCP (Short Circuit), OTP (Over Temperature), NLO (No Load Operation), and SIP (Surge and Inrush) protections. Backed by a 100,000-hour MTBF rating and a 10-year manufacturer warranty, it is built to outlast multiple system upgrades.