What You’ll Find Inside a Massive Water-Cooled Intel 3000W Power Supply

A 3000W power supply often conjures up images of huge metal boxes with noisy fans pumping air over massive heat sinks, but this Intel reference unit blasts that idea out of the water, or rather keeps it cool, due to a water cooling system that keeps everything nice and clean.

Intel engineers designed this beast of a device for data centers and servers, where squeezing as much power as possible into a small space is the name of the game. It accepts a large 240-volt AC and outputs a reasonable 12 volts DC at up to 250 amps, suitable for 3000 wattage.Water flows through the back of the unit via quick-release fittings, carrying heat away without the need for a noisy internal fan or traditional heat sink fins, and the entire thing remains sealed and silent with no internal moving parts, relying on external coolant to keep things from overheating.

Inside, things get a little more tricky because the enclosure is a solid black box with no vents to speak of. When the screws are removed, you’ll discover two chunky circuit boards jammed together with a large cold plate crammed in between. The components all push against the cold plate using thermal pads, and the circulating fluid then transports the heat to the outside world. The configuration works well to split chores, with one board handling power factor adjustment on the input side and the other handling the primary DC-DC conversion bit.

Input protection is the first priority, with fuses, surge arrestors, metal oxide varistors, gas discharge tubes, and common-mode chokes all doing their part to keep unpleasant little shocks from the mains supply from causing issues. Following that, bulk capacitors are used to smooth out the rectified line voltage, ensuring that it is not unsteady or unpredictable. The power factor adjustment step, on the other hand, employs a neat technique known as an interleaved totem-pole topology to reduce ripple and enhance efficiency. The GaN transistors in that part are from Texas Instruments and have a reasonable 600 volt rating. They are also fast-switching (which is good) and low-loss, enabling it to achieve the unit’s 80 Plus Platinum certification

The power is subsequently transferred to the phase-shifted full-bridge section on the other board. Silicon carbide MOSFETs are the high-voltage switching components here, paire with a transformer that graciously lowers down the voltage for us. The litz wire on the main side is wound to reduce signal loss as the frequency increases, while synchronous rectifiers on the secondary side work their magic to provide even greater efficiency. The output filtering is then provided by a large inductor and 9000 microfarads of polymer capacitors, all working together to provide a clean 12 volts DC at the output.

Of course, there have to be some control circuits in there somewhere to keep things running smoothly; a Texas Instruments C2000 microcontroller manages the PFC stage, while a PIC24 monitors overall supervision. To keep things nice and safe, there are digital isolators (which are really brilliant, in my opinion) and auxiliary flyback converters that provide standby power as necessary.

Some of the design choices on show here are quite impressive, as the cold plate design allows the unit to chug out a respectable 2500 watts per liter, as that’s a whopping 250 times more power per liter than the average air-cooled supplies, which might only scrape in at around 800 watts per liter, but using advanced semiconductors like GaN and SiC really helps to keep losses to a minimum. However, it’s the water block that still proves essential at full load where losses total around 300 watts.
[Source]