Zalman's ZM-750HP 750W
The quietest of them all?

Although better-known for its ornate, exotic, and largely silent PC cooling accessories, Zalman has been in the power supply business for some time. It's only fitting, then, that the company's latest ZM-750HP PSU is billed as an ultra-silent offering. Building a quiet power supply is no easy task, and with 750 watts on tap, the ZM-750HP doesn't hold back on the capacity front.

Zalman does hold back a little in the warranty department, though. Coverage is limited to three years. At least you're not paying much of a premium here; the ZP-750HP can be had online for as little as $145—a reasonable price for a 750W unit.

Zalman knows cooling, and the company has selected a 120mm fan to move air through the ZM-750HP. There's also a small heatpipe-fed radiator at the back of the unit, hiding just behind an open metal grill that allows for airflow through the rear.

Of the three modular PSUs in this round-up, only the Zalman hard-wires a string of Serial ATA power connectors to the PSU. That's not an entirely bad idea, since there's certainly no need for all cabling to be modular. Just about any modern system that necessitates a 750W PSU is going to need at least one Serial ATA power plug, anyway.

With just about every PSU maker offering sheathed cables, we're forced to get a little picky here. Props to Zalman for sheathing all of its cables, including sections between connectors. However, that sheathing does pull up about an inch short of each connector. I'll forgive that minor transgression because Zalman also throws a handy three-pin fan adapter into the box. This adapter plugs into a standard 4-pin power plug and provides a pair of three-pin fan connectors: one fed by the 5V line and another with 12V power.

That, folks, is a set of very accurate DC voltages.

The ZM-750HP keeps AC ripple content nice and low, as well. Curiously, ripple on the primary 3.3, 5, and 12V rails drops precipitously at full load, while the 12V PCIe line remains largely unaffected.

With at least 82% efficiency across the board, the ZM-750HP has no problem living up to its 80 Plus certification. In fact, the PSU's 88.9% efficiency under our lightest load is nearly the highest power supply efficiency we've ever measured.