Seasonic Focus Plus 750W Gold PSU Review: The Best Gold Rated PSU Available
Introduction
When it comes to computers, the power supply is the most important component and cutting corners when purchasing a power supply can prove fatal for your system which is why you must make sure you purchase a quality power supply from a reputable company such as Seasonic. Seasonic is known for making the best power supplies in the PC industry and their power supplies are some of the highest quality you can buy. Seasonic's power supply series are comprised of the Prime Ultra, Focus Plus, Focus, M12II and S12II. The Focus Plus series consists of the Gold and Platinum product line, with the Platinum line offering four power supplies ranging in capacity from 550W to 850W while the Gold line goes all the way up to 1000W.
Pricing & Warranty
Today we are reviewing the Seasonic Focus Plus SSR-750FX Gold power supply that retails for $104.99 on Amazon and comes with 10 years of warranty. The SSR-750FX is an 80+ Gold certified PSU which means that it is 90% efficient at 50% load. So in other words, at 50% load, an 80+ Gold PSU will waste 10% energy as heat which is very good. The SSR-750FX features a single +12V rail that can output enough power to feed two high-end graphics cards and still have plenty of room for overclocking your CPU.
There are only a few companies that provide 10 year warranties for their power supplies and Seasonic is one of them. The majority of the manufactures offer 5 year warranties so this shows Seasonic's commitment to their PSU quality and longevity. At the time of writing this review, you can find the SSR-750FX for $105 on Amazon and Newegg which makes it about $5 cheaper compared to other 750W Gold PSUs from other reputable manufactures. This is good for everyone because consumers get good quality PSUs for a good price and Seasonic generates tons of sales buzz thus creating positive word of mouth about their PSUs.
Features
The Focus Plus Gold line comes in a fully modular design which allows you to only use the cables you need thus helping improve case airflow and eliminating unnecessary wires and reducing clutter. Seasonic is using high-quality Japanese brand capacitors that ensure long-term reliability. Another good thing about the Focus Plus line is that it comes in a small 140mm footprint which can help in cases where space is premium.
Seasonic has equipped their Focus Plus series with a 120mm Fluid Dynamic Bearing (FDB) fan with the ability to run in three operational stages: Fanless Mode, Silent Mode, and Cooling Mode. The fan in the power supply turns off for silent operation during idle or low powered activities if the loading condition is below 30%. Seasonic has also included a switch at the back of the power supply which allows users to customize their cooling needs by selecting between the Seasonic S2FC (fan control without Fanless Mode) and the S3FC (fan control including Fanless Mode). This is a high quality fan that is extremely reliable and generates considerably less operating noise and heat than ball bearing fans.
The Seasonic Focus Plus series includes ±3% tight voltage regulation which helps significantly with stability. In other words, think of voltage regulation this way. When your computer is running, the current power draw can suddenly change for your CPU or GPU load. When this happens, the less change in voltage, the better thus resulting in better stability for your computer. Cheap power supplies don't do this very well, and can often damage the components of your computer so be very careful when purchasing some random power supply you find on websites such as Amazon and Newegg.
Most of the really good PSUs out there are rated for 50°C operating temperature but the majority of them are generally rated for 40°C. This is a pretty difficult standard to meet and Seasonic has achieved that with the Focus Plus series and the SSR-750FX comes with a 50°C operating temperature. Seasonic has also implemented a cable-free connection design solution where instead of cables, the back panel and the PCB are connected by a copper plate. This lowers the chance of production errors during manual insertion and also improves power efficiency.
Specifications
| Seasonic SSR-750FX Specifications | |||||
|---|---|---|---|---|---|
| Manufacture: | Seasonic | ||||
| Model: | SSR-750FX | ||||
| Max. DC Output: | 750W | ||||
| 80PLUS: | Gold | ||||
| Over Voltage Protection: | Yes | ||||
| Weight: | 6.80 lbs | ||||
| Efficiency Level: | ETA-A | ||||
| Noise Level: | LAMBDA-A | ||||
| Form Factor: | Intel ATX 12 V | ||||
| Dimensions: | 140 mm (W) x 150 mm (L) x 86 mm (H) | ||||
| Fan Size: | 120 mm | ||||
| Fan Control: | Premium Hybrid Fan Control | ||||
| Fan Bearing: | Fluid Dynamic Bearing | ||||
| Life Expectancy: | 50,000 hours at 40 °C, 15 % - 65 % RH | ||||
| Modularity: | Fully Modular | ||||
| Cable type: | Flat black cables | ||||
| Operating Temperature: | 0 - 50 °C | ||||
| MTBF @ 25 °C, excl. fan: | 100,000 hours | ||||
| AC Input: | Full Range | ||||
| Protection: | OPP, OVP, UVP, OCP, OTP, SCP | ||||
| Safety and EMC: | cTUVus, TUV, CB, CCC, BSMI, EAC | ||||
| Environmental Compliance: | Energy Star, RoHS, WEEE, ErP Lot 6, REACH | ||||
| Warranty: | 10 Years | ||||
| Voltage: | 100 V - 240 V | ||||
| Current: | 10 - 5 A | ||||
| Frequency: | 50 Hz - 60 Hz | ||||
| Load Range | |||||
| Rail | +3.3V | +5V | +12V | -12 V | +5 VSB |
| Max.(Amps): | 20 A | 20 A | 62 A | 0.3 A | 3 A |
| Max.(Power): | 100 W | 744 W | 3.6 W | 15 W | |
| Total Continuous Power: | 750 W | ||||
| Main Connector | 20+4Pin | ||||
| +12V Rails: | Single | ||||
| PCI-Express Connector: | 4 x 6+2-Pin | ||||
| SATA Power Connector: | 8 | ||||
| Connectors: | 1 x ATX connector 20+4 pin (610mm) 2 x 4/8 Pin CPU (650mm) 4 x 6+2 pin PCIe (675mm+75mm) 8 x SATA (450mm+120mm+120mm+120mm) 3 x Peripheral (450mm+120mm+120mm) 1 x FDD (110mm) | ||||
Packaging
The SSR-750FX comes in a simple but elegant box that stands out when you first see it due to the bright yellow color. Looking at the front of the box, we see the Seasonic logo on the top left corner followed by the 'Focus+ Gold' text in the center and '750FX' model number in the bottom right corner.
On the back, you will see a list of the SSR-750FX's features such as the 80Plus Gold rating, DC to DC converter design, +12V output, tight voltage regulation, reliable aluminum solid capacitors, 120mm FDB fan, compact design, fully modular cabling, and a 10-year warranty. Size-wise, the SSR-750FX is 140mm wide, 86mm tall and 150mm long and weighs 6.80 lbs.
Seasonic's packaging is top notch and I've never seen a company take packaging this seriously. We can see that the SSR-750FX is protected by two high density foams as shock absorbent to prevent any accidental damages during shipping. The power supply is enclosed inside a cloth bag that definitely gives it a premium feel to it. Most manufactures package their power supplies in plastic bags so it's nice to see Seasonic go the extra mile with their packaging. There's a void sticker on one of the corners of the PSU and tampering with the PSU of course voids the warranty.
Inside the box you will find a set of Velcro straps, four mounting screws, several zip ties, Focus case badge, an AC power cord, a user's manual and a bundle of modular cables in a separate cloth bag. The manual has all the information you need to know about the power supply such as how to set up your power supply and basic troubleshooting.
The cables are of ample length and you can look at the table above for connector count and for cable lengths. The only thing that I don't like about the cables is that Seasonic has added capacitors to some of the cables (ATX, EPS, PCIe) for extra ripple filtering. Adding capacitors to these cables has made them quite bulky which makes the cables difficult to fold and route around the case but the peripheral cables don't have capacitors in them so they are flat. Flat cables have much greater flexibility to allow for tighter folding and management of cables.
Build Quality
I took a few pictures of the layout and components inside the SSR-750FX to show you guys what it looks like. I'm highly impressed by the internal build quality of the SSR-750FX. It sports a very clean layout and all of the capacitors are high quality. The integration and soldering quality is top notch as we would expect from Seasonic.
The SSR-750FX uses all Japanese capacitors throughout the build. Japanese manufacturers such as Nippon Chemi-Con are known for making excellent capacitors and have a reputation for excellent quality control and are also said to use a refined electrolyte with better sealing capacity that are more resilient to higher temperatures. The primary bulk capacitor is provided by Nippon Chemi-Con and is rated at 400v 560uf 105°C.
Moving on, you will notice that the SSR-750FX is using four heatsinks that help with dissipating the heat from the primary and secondary side which is very good. There's a small PCB where the AC receptacle and power switch are installed which also holds the first part of the EMI suppression filter. So the input filtering begins on this small PCB that has some X and Y capacitors attached to it and then trails onto the main PCB for completion.
The SSR-750FX is featuring a full bridge LLC topology and LLC resonant converter on the primary side while the secondary side uses synchronous rectification and DC-to-DC converters. The wires are color-coded so it is easy to take everything apart and re-house if needed. All of the filtering is handled by several Nippon Chemi-Con capacitors which is great.
Looking at the back of the power supply, we can see that the connectivity is fairly standard. The modular panel includes 11 sockets and the panel is nicely labeled to let you know what each socket is used for.
The SSR-750FX comes with a 120mm Fluid Dynamic Bearing (FDB) fan with a max 2200 RPM and is rated for 0.58A, 73.9 CFM, and 32.4 dBA at 12V. The fan is by Hong Hua and the model number is HA1225H12F-Z and it is connected to the PCB using a 2-pin connector. Fluid dynamic bearings fans have much longer lifespans compared to sleeve bearing fans and this makes them great for power supplies.
Test Methodology
Our goal here is to simulate realistic loading conditions to see how well the PSU can maintain the various output voltages while operating under different loads. All of the testing is conducted at an ambient temperature of 22°C. These tests will be performed at several load levels, from low (100W) to high (700W) or higher depending on the PSU. We are looking for results as close to 12V, 5V and 3.3V as possible. We are also measuring the PSU noise levels during our load testing. Sound pressure level readings were measured from about 100cm away from the PSU.
Below is a table listing the tolerances for each power supply voltage rail based on the ATX specification version 2.2. We have also included a table with various dBa ratings to help describe the various noise levels based on real world situations.
| Power Supply Voltage Tolerances | |||
|---|---|---|---|
| Rail | Tolerance | Min. Voltage | Max. Voltage |
| +3.3V | ± 5% (±0.165V) | +3.135V | +3.465V |
| +5V | ± 5% (±0.25V) | +4.75V | +5.25V |
| -5V | ± 10% (±0.50V) | -4.50V | -5.50V |
| +12V | ± 5% (±0.60V) | +11.40V | +12.60V |
| -12V | ± 10% (±1.20V) | -10.80V | -13.20V |
| Noise Levels (dBA) | |
|---|---|
| Lawn Mower: | 90 dBA |
| Vacuum Cleaner: | 80 dBA |
| City Traffic: | 75 dBA |
| Conversation: | 65 dBA |
| Air Conditioning: | 60 dBA |
| Floor Fan: | 50 dBA |
| Electric Hum: | 45 dBA |
| Refrigerator Hum: | 40 dBA |
| Rustling Leaves: | 30 dBA |
| Pin Falling: | 15 dBA |
| Just Audible: | 10 dBA |
| Threshold of Hearing: | 0 dBA |
Results
| Seasonic Focus Plus 750W Load Tests | ||||||
|---|---|---|---|---|---|---|
| DC Load | +3.3V | +5V | +12V | Efficiency | Fan Speed | PSU Noise |
| 100W | 3.30V | 5.08V | 12.04V | 89.2% | 0 RPM | <10 dBA |
| 200W | 3.29V | 5.04V | 12.02V | 90.7% | 0 RPM | <10 dBA |
| 300W | 3.30V | 5.07V | 12.08V | 89.4% | 490 RPM | 12 dBA |
| 400W | 3.29V | 5.03V | 12.07V | 88.5% | 640 RPM | 17 dBA |
| 500W | 3.30V | 5.03V | 12.04V | 90.3% | 1070 RPM | 24 dBA |
| 600W | 3.30V | 5.04V | 12.03V | 89.8% | 1350 RPM | 31 dBA |
| 700W | 3.31V | 5.09V | 12.02V | 90.2% | 1930 RPM | 39 dBA |
The SSR-750FX performed excellent in our tests and the voltage regulation was outstanding. The SSR-750FX stayed within ±1% of the ATX guidelines. As far as noise levels go, the SSR-750FX is very quiet in low and medium loads. During low loads, the fan doesn't spin so it's silent and during medium loads, the fan is still quiet. The fan does become noticeable during very high loads.
Conclusion
For those looking to build highly efficient systems in small footprints, the SSR-750FX is definitely one of the best PSUs you can buy at the moment. It has everything you can ask for in a high quality PSU and then some. The interior design of the Seasonic SSR-750FX is modern and the integration quality is top-notch. It sports a clean and elegant build quality that has ample power to drive a high end gaming computer with no problem.
The SSR-750FX features a silent 120mm FDB fan with intelligent semi-fanless operation which makes it great for quiet home or office use. If the loading condition is below 30%, the fan will remain off for silent operation. The trend for small form factor computers has been increasing over the years due to the hardware components becoming more efficient and Seasonic is helping to drive the efficiency movement by releasing the Focus Plus series of power supplies in compact designs.
One thing to keep in mind about the SSR-750FX is that the ATX, EPS, and PCIe cables have capacitors at the component end.
This has allowed Seasonic to make the PSU smaller by moving the capacitors to the cables but
it has also made the cables much harder to route and fold.
Having capacitors in the cables also eliminates the ability to sleeve the cables which could be an issue to users who are into modding.
Pros:
+ Price
+ High Build Quality
+ Quiet FDB Fan
+ Fully Modular
+ Fantastic Packaging
+ 10 Year Warranty
+ High Efficiency
+ Compact Design
Cons:
- Cables Are A Little Stiff
Seasonic has done a fantastic job with the SSR-750FX and the compact design, long warranty coverage, high efficiency and high build
quality makes it a fantastic PSU. The 10 year warranty shows how confident in the quality and reliability of their product Seasonic is.
Overall, the Seasonic SSR-750FX easily deserves our gold award.
Final Score 9.8
