Seasonic Prime Titanium 650W PSU Review

Seasonic jumps onto the 80 PLUS Titanium wagon with three new units that belong to its Prime family. The 650 W model is under our scope today. Besides high efficiency, it also offers great performance, quiet operation, and nice looks.

During this year's CES, Seasonic shared many details about its flagship Prime line-up, which includes three product families with 80 PLUS Titanium, Platinum, and Gold efficiency ratings. The Titanium range will include five members with capacities ranging from 600 W to 1 kW, and the lowest-capacity model will feature fanless operation. The Platinum Primes will number five in total between 650 W and 1.2 kW max power. Finally, there will be as many Gold Prime models as Platinum ones, covering the same capacity range. According to Seasonic's roadmap, all Prime models, 15 in all, will be available by the end of this year.

Aside from the Prime family, Seasonic plans to introduce a more budget-oriented one called Focus. There will be two Platinum Focus units, with 550 W and 650 W capacities, and four Gold ones with 450 W to 750 W maximum power. If all goes as planned, the Focus units will be released some time before 2017.

As you can see, Seasonic is quite busy. It's making the necessary preparations for a strong comeback, not only in the high-end space currently dominated by Super Flower, but also in the mid-range segment more interesting to budget-minded enthusiasts. 

The 750 W and 650 W Titanium Prime models are already available, and soon the 850 W version will surface as well. For now, we're reviewing the 650 W SSR-650TD. Aside from high efficiency, this PSU also promises increased reliability thanks to its Japanese caps and fluid dynamic bearing (FDB) fan. According to Seasonic, the Hong Hua cooler has a lifetime of 40,000 hours at 40 °C. Compared to the specs of other FDB fans, that's not particularly impressive. However, most fan vendors rate their products at much lower ambient temperatures, which isn't representative of a power supply's real-world internal conditions.

The SSR-650TD's other performance highlights include a hold-up time that Seasonic claims exceeds 30 ms, an improved transient response for the +12V rail, ripple that doesn't surpass 20 ms on any rail, and tight load regulation. Seasonic says its Prime units only have 0.5% voltage drops on the primary rails, a performance level we don't even see in the high-end category very often. Even better is the 10-year warranty. This is the first time we've seen Seasonic cover a product for so long, showing that the company clearly trusts its newest platform.


Besides Titanium-class efficiency this Prime unit also has a 50 °C temperature rating for continuous full power delivery, and it is covered by a complete set of protections. Modular cabling is considered a necessary feature for every high-end PSU nowadays, and the FDB fan is a big asset when it comes to reliability. The semi-passive mode can be disengaged through a push button on the front side of the PSU, should you prefer normal fan operation. Finally, the dimensions of the Titanium Prime models are a little larger than normal; this model is 17 cm deep.

Power Specifications

Max. PowerAmps20205430.3
Total Max. Power (W)650

The single +12V rail can deliver the unit's full power alone, while the minor rails are limited to 100 W maximum power output. Fortunately, that's enough for any modern system. At least the 5VSB rail is a little stronger than most, offering 15 W capacity.

Cables And Connectors

Modular Cables
DescriptionCable CountConnector Count (Total)
ATX connector 20+4 pin (610 mm)11
4+4 pin EPS12V (650 mm)22
6+2 pin PCIe (675 mm+80 mm)24
SATA (460 mm+120 mm+120 mm+120 mm)14
SATA (360 mm+120 mm)12
Four-pin Molex (460 mm+120 mm+120 mm)13
Four-pin Molex (360 mm+120 mm)12
FDD Adapter (+101 mm)11

All provided cables are long enough, and this is the first time that we see a PCIe cable with its first connector installed at a longer distance than the EPS connector. However, we don't mind at all. The only negative we can find is the short distance between peripheral and SATA connectors, which can lead to compatibility problems in some cases. In our experience, you want at least 15 cm between them. Finally, all of the cables use standard 18-gauge wires.

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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