Seasonic Focus Plus Platinum 750 PSU Review: Efficiency On A Budget

Seasonic released a ton of new power supplies last year, and we're still trying to get them all tested. Its Focus Plus Platinum series sits atop the Focus line-up and features four members with capacities ranging from 550W to 850W. They all boast 80 PLUS Platinum and ETA-A efficiency certifications, employ fully modular cabling, and are backed by a 10-year warranty. Moreover, the Focus Plus Platinum PSUs sport super-compact dimensions, with even the flagship 850W model measuring 140mm deep.

It is nice to see PSUs built with high power density and quiet operation in mind. Usually, small enclosures and lots of capacity necessitate faster fan speeds, resulting in more noise. Thanks to the Focus Platinum family's high efficiency levels and smart layout, though, there is no need for increased airflow. Under normal operating conditions, these PSUs utilize relaxed fan profiles.

The Focus Plus Platinum 750 or SSR-750X is today's test subject. It's the second-strongest Focus Plus Platinum model, capable of supporting a potent gaming PC with a pair of high-end graphics cards. Thanks to its two EPS cables, it also works with workstation-oriented motherboards that need more power for their CPUs.

Available for just over $110 when this review was written, the SSR-750X looks like a solid value; the competition is going to have a tough time matching it. Somehow, Seasonic is able to keep its price down without negatively affecting performance or build quality. This manufacturer clearly prefers selling Focus-branded PSUs on its own rather than offering the platform to other companies, so it doesn't have a problem managing its competitive position.

Specifications

Manufacturer (OEM)Seasonic
Max. DC Output750W
Efficiency80 PLUS Gold, ETA-A (88-91%)
NoiseLAMBDA-A+ (15-20 dB[A])
Modular✓ (Fully)
Intel C6/C7 Power State Support
Operating Temperature (Continuous Full Load)0 - 50°C
Over Voltage Protection
Under Voltage Protection
Over Power Protection
Over Current (+12V) Protection
Over Temperature Protection
Short Circuit Protection
Surge Protection
Inrush Current Protection
Fan Failure Protection
No Load Operation
Cooling120mm Fluid Dynamic Bearing Fan (HA1225M12F-Z)
Semi-Passive Operation✓ (selectable)
Dimensions (WxHxD)152 x 86 x 142mm
Weight1.63 kg (3.59 lb)
Form FactorATX12V v2.4, EPS 2.92
Warranty10 Years

The PSU offers low overall noise, earning a LAMBDA-A+ certification from Cybenetics. Strangely, the 650W Focus Plus Platinum only reaches the LAMBDA-A- level since its acoustic output exceeds 25 dB(A). Either its fan control circuit is badly tuned or the SSR-750PX simply benefits from a more relaxed fan profile.

All of the other specifications are top-notch. Again, it's amazing that Seasonic can deliver such strong performance in a compact footprint.

Power Specifications

Rail3.3V5V12V5VSB-12V
Max. PowerAmps20206230.3
Watts100744153.6
Total Max. Power (W)750

A single +12V rail serves up 62A maximum current output. The minor rails have sufficient capacity to satisfy the demands of modern PCs, while the 5VSB rail can deliver up to 3A on paper, and double that in real-world testing.

Cables & Connectors

Modular Cables
DescriptionCable CountConnector Count (Total)GaugeIn Cable Capacitors
ATX connector 20+4 pin (600mm)1118-22AWGYes
4+4 pin EPS12V (650mm)2218AWGYes
6+2 pin PCIe (680mm+80mm) 2418AWGYes
SATA (450mm+110mm+110mm+110mm)2818AWGNo
Four-pin Molex (450mm+120mm+120mm)1318AWGNo
FDD Adapter (+105mm)1122AWGNo
AC Power Cord (1370mm) - C13 coupler1118AWG-

Seasonic equips this PSU with lots of cables, including two EPS, four PCIe, and eight SATA connectors. Some folks might want a few more four-pin Molex connectors. But as long as you keep power consumption low on the ones Seasonic gives you, splitters are a viable option for extra devices. There is also a Berg adapter provided, in case you need it.

In order to offer top-notch ripple suppression, the main ATX cable, along with the EPS and PCIe ones, use in-cable capacitors. Still, we're not huge fans of in-cable caps because they make cables bulky and difficult to route.

The SSR-750PX's cables are shown in the photos above.

Power Distribution

Since this PSU features a single +12V rail, we do not have anything to say about its power distribution.

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