The Lian Li RBO750B has emerged as a compelling choice for budget-conscious system builders. It is a 750W ATX 3.1 power supply, available at $69.99, and reportedly prioritises modern connectivity and solid electrical performance over luxury modular cabling.
The unit is rated 80 PLUS Bronze. However, testing revealed efficiency levels nearing the Silver tier. This combination makes it a strong contender for reliable power in current-generation component setups.
Measuring 150 x 150 x 86 mm, the RBO750B is cooled by a 135mm Hong Hao hydraulic bearing fan. The fan operates up to 1,600 RPM, maintaining a rated noise level of 40.1 dBA.
Internally, the PSU utilizes a Helly Technology platform. This design incorporates an Active PFC, a Half-Bridge LLC resonant converter, and a DC-to-DC step-down architecture, defining it as a modern topology for its Bronze tier.
Stability is anchored by a single Toshin Kogyo 105°C main capacitor. This component, rated at 420V / 470µF, contributes to the unit’s stability and thermal endurance.
Connectivity includes a native 12V-2×6 cable, designed specifically for powering modern GPUs without requiring adapters. Standard fixed cables include a 20+4-pin motherboard connector, two 4+4-pin CPU EPS connectors, two 6+2-pin PCIe cables, five SATA connectors, and two Molex connectors.
The primary compromise in the unit is its non-modular cabling. To address potential cable clutter, Lian Li integrated cable-routing loops along three sides of the chassis. Users can use included Velcro straps to neatly cinch unused wires against the unit.
In a nearly 13-hour stress test, the RBO750B powered an AMD Ryzen 9 7950X and an RTX 3090. The unit achieved 88.4% efficiency at approximately 50% load (a 375W AC draw). This efficiency rating exceeded the 85% Bronze requirement and approached the 89% Silver benchmark.
Throughout the burn-in, the 135mm fan remained silent, staying below audible noise thresholds inside a closed chassis. Voltage stability was consistently high. The native 12V-2×6 cable also eliminated the need for messy PCIe splitters.
Performance reviews assigned the RBO750B an overall score of 90%. Specific sub-scores noted 90% for Performance and 90% for Quality, alongside 85% for Features and 95% for Value.
Reviewers recommended the unit for budget system builders. If users require ATX 3.1 support without incurring extra costs for modular cabling, the RBO750B provides reliable 750W power for modern components at a $70 price point.
