KHACHIMO 1U 300W 400W ATX Power Supply SD-3400U

1U ATX supply for compact builds

The KHACHIMO SD-3400U is a 1U form-factor ATX power supply rated at 300 W continuous with a 400 W peak capacity. It targets builders assembling low-profile desktops, rack-mount servers or space-constrained workstations where standard-height units will not fit. Buyers needing higher sustained wattage for multi-GPU configurations should look elsewhere.

Efficiency and sleep-state limits

An 80 PLUS Gold rating confirms high efficiency at typical loads, reducing waste heat and lowering operating costs over time. Modern Standby compatibility allows the unit to enter and exit low-power sleep states rapidly, but the feature only functions when the motherboard and operating system also support the standard. Systems without Modern Standby firmware will not benefit from the faster wake times.

Cooling behaviour and topology

Zero RPM fan mode stops the fan completely at low and medium loads, delivering near-silent operation during office work or idle periods. Resonant LLC topology combined with DC-to-DC conversion supplies clean, stable voltages and reduces coil whine, though audible noise will return once the fan spins up under heavier demand. The 1U chassis dictates a small fan diameter, so airflow density is higher than in full-height units.