Seasonic PRIME 650W Platinum PSU Review

1. Introduction2. Bundle & Cabling3. External4. Internal5. Testing Methodology & Results6. Closing Thoughts7. View All Pages

Today we finalise our coverage of the latest Seasonic PRIME Platinum platform by analysing the 650 watt model in the range. This fully modular, 80 Plus Platinum certified model is priced at £155 in the United Kingdom, around £30 less expensive than the PRIME 650W Titanium supply which we reviewed back in August 2016.

High grade Platinum power supplies are expensive. At £155, this is one of the most cost effective units in the new Seasonic range, but it is still a fair chunk of cash for a 650 watt supply.

Like other models in the range it ships with a low noise Fluid Dynamic Bearing cooling fan incorporated and we hope Seasonic have over specified this unit to similar levels as the 650W Titanium unit we analysed last summer.

650W PRIME Platinum Specifications:

– Model name: SSR-650PD
– 80 PLUS®: Platinum
– Form Factor: Intel ATX 12 V
– Dimensions: 170mm (L) x 150mm (W) x 86mm (H) +/-1 mm
– Fan Size: 135 mm
– Fan Control: Premium Hybrid Fan Control
– Fan Bearing: Fluid Dynamic Bearing
– Life Expectancy: 70,000 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: 150,000 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

Review photography handled in house at KitGuru with a Leica S series medium format camera and S series prime lens. Please do not use any of the images within this review without express permission.

The same shiny box as all the other units in the range. We see a 10 year warranty sticker bottom left. This has however recently been upgraded to a whopping 12 years which is the best in the industry. You can read about the 12 year Seasonic warranty upgrade (HERE).

The rear of the box highlights a basic overview of some of the main features alongside a high resolution image of the power supply itself.

The power supply ships protected between thick blocks of foam, and is encased inside a soft felt bag, shown in the image above left.

Seasonic fully load this box with a wealth of extras. You get a modular cable bag, resealable plastic wallet, regional specific power connector, two kinds of cable ties, a case badge, branded sticker, an installation guide, mounting screws and user manual.

The Seasonic power supply is a pure modular design. The cables are a mixture of sleeved (ATX, CPU and PCIe) and flat ribbon style (peripherals), for ease of routing.

Connector	Number of Connectors	Cable Lengths
Main Power (20/24 pins)	1	1 x 610 mm
CPU (4/8 pins)	1	1 x 650 mm
PCIe (6/8 Pins)	4	2x 675 + 75 mm
SATA	6	1 x 450 + 120 + 120 + 120 mm 1 x 350 +120 mm
Peripheral	3	1 x 450 + 120 + 120 mm
Floppy	1	1 x 101 mm

This 650 Watt supply has 4 PCIe connectors, to support 2 way SLi and Crossfire. There are 6 SATA connectors. The higher spec 850 Watt model has 6 PCIe connectors and 10 SATA connectors. The 650Watt supply has a single CPU power connector, not two – as on the higher models in the range.

The PRIME power supplies are very nicely finished. The paint work is deep and consistent and prove difficult to scratch. The Platinum range doesn't however have the additional shiny panel that rests around the PRIME logo in the center of the fan.

The large cooling fan is behind the grill above. We will take a closer look when we open the supply later in the review.

This side of the unit is home to the power socket, power switch and Hybrid fan switch.

This Hybrid mode allows the fan to be disabled completely when the unit drops to a specific temperature threshold. Seasonic claim the Hybrid Fanless mode works up to:

• Approximately 50 % (±5 %) of system load at 25 °C.
• Approximately 30 % (±5 %) of system load at 40 °C.

All the other supplies we have reviewed in the Platinum PRIME range have the same modular connector layout. This unit is different however as there are now 2 horizontal rows, and not 3.

The CPU/ PCI E connectors are in two rows of two on the left side of the connector bay. Peripheral connectors are in a single row of four top right, with the motherboard connectors in a row bottom right.

Seasonic PRIME 650W Platinum Power Supply
DC Output	+3.3V	+5V	+12V	-12V	+5Vsb
Max Output	20A	20A	54A	0.3A	2.5A
Total Power	100W		648W	3.6W	12.5W
	650 Watts

This 650W power supply can deliver 54A via the +12V rail. This is a drop from 70V from the previous 850 watt unit we reviewed last week.

Seasonic are using a Hong Hua 135mm fan, Model number HA13525H12F-Z – the same model featured in the PRIME 850W, 1000W and 1200W Platinum supplies. This is a Fluid Dynamic Bearing Fan selected for low noise characteristics. Regular readers may recall that the Seasonic Snow Silent 750W unit shipped with a smaller 120mm fan from the same company so its a good move that Seasonic are adopting larger fans.

Below - a High Resolution Gallery of the internal layout of the Seasonic PRIME 650W Platinum

Soldering quality throughout is excellent and Seasonic have reduced clutter inside thanks to their new cable free connection design. Due to the very high levels of efficiency there is no need to include a plethora of heatsinks throughout the design, so we are left with a couple of heatsinks in key placements which should be more than adequate.

No surprise, but Seasonic are using high grade 105c rated Japanese capacitors in both primary and secondary stages which is always reassuring to see. No TEAPO garbage in this supply.

The two primary Nippon Chemi Con capacitors are 105c rated and 400v 220uF to produce a total of 440uF. Checking back with our review of the Titanium PRIME 650W power supply from August 2016, we can see Seasonic massively over specified that unit, with two 450uF primary capacitors in the design to deliver a total of 900uF!

Correctly testing power supplies is a complex procedure and KitGuru have configured a test bench which can deliver up to a 2,000 watt DC load. We run at 35c in our environment to greater reflect warmer internal chassis conditions.

We use combinations of the following hardware:
• SunMoon SM-268
• CSI3710A Programmable DC load (+3.3V and +5V outputs)
• CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4)
• Extech Power Analyzer
• Extech MultiMaster MM570 digital multimeter
• Extech digital sound level meter
• Digital oscilloscope (20M S/s with 12 Bit ADC)
• Variable Autotransformer, 1.4 KVA

We test in a single +12V configuration.

DC Output Load Regulation
Combined DC Load	+3.3V		+5V		+12V		+5VSB		-12V
	A	V	A	V	A	V	A	V	A	V
65W	0.92	3.35	0.88	5.03	4.42	12.07	0.50	5.02	0.20	-12.03
130W	1.63	3.35	1.65	5.03	9.15	12.06	1.00	5.02	0.20	-12.02
325W	2.93	3.34	3.05	5.02	24.25	12.06	1.50	5.01	0.20	-12.02
490W	4.01	3.34	4.10	5.02	36.90	12.05	2.00	5.01	0.30	-12.02
650W	5.00	3.34	5.30	5.00	49.67	12.03	2.50	5.01	0.30	-12.03

Load regulation is top drawer and well within 1%.

Seasonic PRIME 650W Platinum	Maximum Load
	712W

We managed to get the PSU to deliver 712 watts before it would shut down, delivering around 62 watts more than the rated specifications.

Next we want to try Cross Loading. This basically means loads which are not balanced. If a PC for instance needs 500W on the +12V outputs but something like 30W via the combined 3.3V and +5V outputs then the voltage regulation can fluctuate badly.

Cross Load Testing	+3.3V		+5V		+12V		-12V		+5VSB
	A	V	A	V	A	V	A	V	A	V
590W	1.0	3.35	1.0	5.02	48.0	12.02	0.2	-12.03	0.50	5.01
145W	12.0	3.31	15.0	5.01	2.0	12.06	0.2	-12.03	0.50	5.00

The unit passed our cross load test without any problems. It was hit with 48A on the +12V rail and it held at 12.02.

We then used an oscilloscope to measure AC ripple and noise present on the DC outputs. We set the oscilloscope time base to check for AC ripple at both high and low ends of the spectrum. ATX12V V2.2 specification for DC output ripple and noise is defined in the ATX 12V power supply design guide.

ATX12V Ver 2.2 Noise/Ripple Tolerance
Output	Ripple (mV p-p)
+3.3V	50
+5V	50
+12V1	120
+12V2	120
-12V	120
+5VSB	50

Obviously when measuring AC noise and ripple on the DC outputs the cleaner (less recorded) means we have a better end result. We measured this AC signal amplitude to see how closely the unit complied with the ATX standard.

AC Ripple (mV p-p)
DC Load	+3.3V	+5V	+12V	5VSB
152W	5	5	5	5
270W	5	5	15	5
400W	5	5	15	5
523W	10	5	20	10
650W	10	10	25	10

Ripple suppression is excellent with both +3.3V and +5V rails peaking at 10mV under full load conditions. The +12V rail peaks at 25mV when load is driven to 100%.

Efficiency (%)
152W	90.7
270W	94.1
400W	93.6
523W	93.1
650W	91.2

Efficiency is excellent, peaking at just over 94% and dropping to 91.2% at full load.

We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components. Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635.

Today to test the Power Supply we have taken it into our acoustics room environment and have set our SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) one meter away from the unit. We have no other fans running so we can effectively measure just the noise from the unit itself.

As this can be a little confusing for people, here are various dBa ratings in with real world situations to help describe the various levels.

KitGuru noise guide

10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refrigerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 Player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum

Noise (dBA)
152W	<28.0
270W	<28.0
400W	30.8
523W	33.8
650W	35.7

Noise levels are low throughout the load range. At full load the fan spins up a little, hitting 35.7dBa. This will likely be masked by a few case fans.

Temperature (c)
	Intake	Exhaust
152W	36	39
270W	39	43
400W	42	48
523W	44	51
650W	47	58

The very high efficiency levels of the power supply ensure that the fan never has to work that hard – its a cool running unit as well.

Maximum load	Efficiency
712 watts	90.5

At 712 watts, the efficiency level measures 90.5%. Not a practical situation to be running 24/7, but worth noting.

The Seasonic PRIME 650W Platinum is another fantastic power supply from a company who can do very little wrong in recent years. The build quality is exemplary and technically it is difficult to find fault with this unit.

Load regulation is stellar and the power supply exhibited no issues when dealing with the intensive cross load test. Ripple suppression is also noteworthy and we recorded a >94% peak efficiency. Thanks to the adoption of a high grade FDB fan noise levels are never a concern, which is important.

On an appearance level, the Platinum range of power supplies are finished in a plain black, whereas the more expensive Titanium units have a silver plate around the fan which adds a little bit of pizazz to the proceedings.

Seasonic have not cut corners by adopting cheaper Chinese components – they tend to use Nippon Chemi Con Japanese 105c caps in all their units, and the 650W Platinum is no different. By recently raising their warranty from 10 years to 12 years, they have also made a public statement about the quality of their units, and how long they are standing by each product.

While the Platinum 650 Watt power supply is undoubtedly impressive, reviewing this product has raised a somewhat interesting point for me. Last year I reviewed the Seasonic PRIME 650 watt Titanium and at the time I really didn't notice just how much they had over specified the unit.

The two primary stage Nippon Chemi Con capacitors in the Platinum model reviewed today deliver a total of 440uF. The Titanium model has two significantly larger capacitors which can output 900uF. The Titanium model could actually output almost 850 watts before switching off, while this Platinum version was closer to 720 watts before shut down. This means that the capacitors in the Titanium unit are running at a much lower percentage of capacity under identical load conditions, which likely is helping improve the overall proficiency of the power delivery and ripple suppression.

As listed on Overclockers UK, you pay £30 extra for the more proficient Titanium 650W PRIME unit, and while the Platinum unit delivers the goods, I would likely spend the extra £30 myself for the class leading Titanium unit.

Buy the Seasonic PRIME 650 Watt Platinum power supply from Overclockers UK for £154.99 HERE.

Buy the Seasonic PRIME 650 Watt Titanium power supply from Overclockers UK for £184.99 HERE.

Discuss on our Facebook page, over HERE.

Pros:

• 12 year warranty.
• technically solid.
• quiet under load.
• fully modular.
• high quality finish.
• 105c Japanese capacitors.
• ripple suppression and load regulation rate highly.

Cons:

• expensive.
• Falls some way short of the slightly more expensive Titanium 650W.

KitGuru says: The Seasonic PRIME 650W Platinum is another great power supply from a company who can do no wrong lately. It does fall a little short when compared directly to the more expensive PRIME 650W Titanium unit however.

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