Cooler Master V Series 700W (V700) PSU Review

1. Introduction2. Cooler Master V Series 700W (Bundle/Cabling)3. Cooler Master V Series 700W (External)4. Cooler Master V Series 700W (Internal)5. Cooler Master V Series 700W (Super High Res Gallery)6. Testing Methodology and Results7. Closing Thoughts8. View All Pages

Today we are looking at a high end power supply from Cooler Master, the V Series 700W. This range comprises a 750W, 850W and 1000W unit. We reviewed the 1000W unit back in May this year. These are all pure modular designs with 80 Plus Gold Certification and a full five year warranty.

Cooler Master have paired up with several OEM partners in the past. Enhance have been one of their key partners, featuring in many of their big selling, budget oriented power supplies. The Cooler Master V Series is however based on the superb high end Seasonic KM3 platform, a Kitguru award winner.

• Fully modular cable design incorporates a single 1000W +12V output that delivers up to 58A.
• 80 PLUS Gold certified: up to 93% efficiency @ 50% load
• Silent 135 mm FDB fan for lower noise and longer lifespan
• Four PCI-E 6+2 pin connectors to support high-end GPUs
• 100% high quality Japanese capacitor ensures performance and reliability.
• Reliable 5 year warranty

The Cooler Master V Series 700W ships in a lovely looking box featuring a moody shot of the power supply alongside some product information and specifications.

Inside, the power supply ships protected between thick foam, with the accessories at the side. Cooler Master wrap the unit in a felt bag as shown above.

The modular cabling is supplied in a nylon bag, alongside a regional specific power plug and mounting screws. There is also a little sheet of paper which presents a basic overview of the power supply.

The cabling is 18AWG rated and apart from the main ATX cable they are all the flat ribbon style which has proven popular with the enthusiast audience in the last couple of years.

They are easier to route and can help improve airflow, which is always a bonus.

Cable (modular)	Connectors
MB 20+4 pin	x1 (600mm)
6+2 pin PCIe	x4 (600mm + 100mm)
4+4 pin EPS12V/ATX12V	x1 (680mm)
SATA	x9 (450mm+100mm)
MOLEX	x2 (450mm+100mm)
MOLEX FDD	x2 (450mm+100mm) x1 (+100mm)

The V700 ships with four PCI E cables, enough for a demanding 2 way SLI or Crossfire configuration. The cables are all long length which is beneficial. The CPU 4+4 cable for instance is 680mm long, meaning it will work well with the tallest chassis currently available. The V700 has a single +12V rail.


The Cooler Master V700 is an attractive looking power supply, finished in a gray and black livery. The name of the supply is presented along the sides, as shown in the image above.

The unit passed our ‘screwdriver’ stress test, which involves running a Philip’s head driver down the side of the chassis with weak to modest pressure. How often have you accidentally hit a power supply with some tools during a system build phase?

The paintwork didn’t scratch or mark at all. It is a very resilient finish.

A large black fan resides behind the black grill with company name sticker in the middle. We will have a closer look at the fan shortly, when we crack it open.

One side of the chassis is vented to ensure good airflow under load. There is a switch and power connector beside the grill, underneath a company logo.

The other side of the supply is home to the modular connectors, which are clearly labelled. The peripheral connectors are all mounted vertically underneath the CPU and PCI-E connectors.

Cooler Master V Series V700 (700W) PSU
DC Output	+3.3V	+5V	+12V	-12V	+5Vsb
Max Output	25A	25A	58A	0.5A	3A
Total Power	125W		696W	6W	15W
	700W

The single +12V rail can deliver 58A which is 696W of the total output. Both +3.3V and +5V rails can deliver 25A each – identical to the more expensive 1000W version in this specific series.

The fan is a Protechnic MGA12512XF-O25. This is a Fluid Dynamic Bearing model which has a much longer life cycle compared to ball bearing units. They also tend to produce less noise. This is the exact same fan that the company are using in their V1000 unit.

The Seasonic OEM design is based around their high grade KM3 platform.

The primary side uses full bridge topology with a LLC resonant converter. The secondary side uses synchronous rectification along with DC-DC converters which produce the minor rails.

Soldering quality throughout this design is exceptional.


This design uses a sealed PCB which is there to improve EMI interference behind the AC receptacle. The transient filtering stage components include a single X cap, a CM choke and four Y caps. There are other transient filtering components on the main PCB, an MOV, two CM chokes and two pairs of Y and X caps.

The design uses a Champion CM6901 LLC resonant controller on a vertical PCB. There are fets here which regulate the +12V rail. Two heatsinks are placed to help cool down the fets. The Seasonic design uses some high grade Chemi-Con polymer caps for filtering the +12V rail. The VRMS that generate the minor rails are installed on the modular PCB. At the front of the PCB are a handful of polymer capacitors by Chemi-Con, and these are used to filter the DC outputs.

The two primary Japanese capacitors are rated 420V, 270uF @ 105c. These are high grade capacitors designed to deal with a lot of heat output.

On this page we present some super high resolution images of the product taken with the 24.5MP Nikon D3X camera and 24-70mm ED lens. These will take much longer to open due to the dimensions, especially on slower connections. If you use these pictures on another site or publication, please credit Kitguru.net as the owner/source.

Additional technical assistance: Peter McFarland and Jeremy Price.

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. Due to public requests we have changed our temperature settings recently – previously we rated with ambient temperatures at 25C, we have increased ambient temperatures by 10c (to 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

DC Output Load Regulation
Combined DC Load	+3.3V		+5V		+12V		+5VSB		-12V
	A	V	A	V	A	V	A	V	A	V
174W	3.27	3.33	3.25	5.05	11.55	12.05	0.76	5.03	0.12	-12.03
352W	7.55	3.33	7.55	5.04	23.08	12.04	1.52	5.03	0.25	-12.03
525W	11.27	3.33	11.29	5.03	34.53	12.02	2.26	5.02	0.37	-12.04
700W	15.05	3.32	15.05	5.02	46.64	12.01	3.02	5.01	0.50	-12.04

The Cooler Master V Series 700W delivers excellent regulation with very little droop on any of the rails. They all hold steady with very minimal fluctuation, even at full load.

Cooler Master V Series 700W PSU	Maximum Load
	844W

We managed to squeeze 844W from the PSU before it would shut down safely. That is a very healthy output above the rated 700W.

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.

Combined DC Load	+3.3V		+5V		+12V		-12V		+5VSB
	A	V	A	V	A	V	A	V	A	V
590W	1.0	3.33	1.0	5.05	48.0	11.99	0.2	-12.02	0.5	5.02
190W	18.2	3.31	20.1	4.99	2.0	12.05	0.2	-12.01	0.5	5.00

Cross load results are class leading as we would expect from the KM3 platform. All rails held close to nominal values, regardless of the demand.

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
174W	10	5	15	10
352W	10	10	20	15
525W	15	20	25	15
700W	15	20	30	15

Ripple suppression is also excellent, with the +3.3V and +5V output peaking at 15mV and 20mV respectively. The +12V output peaks at 30mV which is well within the rated industry tolerance parameters. Fantastic results.

Efficiency (%)
174W	87.75
352W	92.35
525W	91.45
700W	89.24

Efficiency is excellent, peaking over 92 percent at 50 percent load. At full load this drops to just over 89 percent efficiency.

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 Digital Sound Level Noise Decibel Meter Style 2 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 Refridgerator
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)
174W	<28.0
352W	<28.0
525W	30.8
700W	32.5

This is an exceptionally quiet power supply, not registering on our equipment until around 450W load is demanded. Even at full load it is barely audible which will prove popular with the demanding enthusiast audience.

Temperature (c)
	Intake	Exhaust
174W	36	39
352W	38	44
525W	42	51
700W	47	57

The internal temperatures are maintained well, rising to a maximum 10c above ambient at full load in our test environment.

Maximum load	Efficiency
844W	86.1%

We measured the efficiency beyond the rated limits of the supply and recorded 86.1% at 834W. Its not a real world everyday rating, but interesting regardless.
The Cooler Master V Series 700W is a fantastic power supply, based around the flagship Seasonic KM3 platform.

No power supply delivers perfect results, but the KM3 range exhibits no weaknesses and they have all delivered stable, high grade power for an enthusiast system. All of these commendable characteristics obviously carry over into the Cooler Master V Series.

Aesthetically the Cooler Master V700 is suitably impressive. The finish is resilient, surviving our ‘stress test' and the modular cable connectors all fit nicely and lock in place as we would expect.

The ribbon style cabling will appeal to the enthusiast audience as they are easy to route and don't block front to back airflow inside a chassis. It is also reassuring to note that the unit ships well protected inside a soft felt bag.

As we have said before, the KM3 series delivers class leading load regulation. Our intensive cross load tests didn't cause a single problem for the unit as it delivered almost nominal results. Ripple suppression is stellar and the V Series 700W fell well within the industry rated specifications. The +3.3V and +5V output peaked between 15mV and 20mV respectively and the +12V peaked at 30mV.

The Cooler Master V Series 700W is over specified internally, we managed to get almost 850W out of the power supply before it safely shut down. When this is combined with the non aggressive fan profile it will also suit a power user wanting to build a quiet system, even with high grade components throughout.

Up to around 600W we would be hard pressed to even hear the fan spinning at all. Those building a high grade media centre would be advised to check this unit out, due to the pure modular design and low noise levels.

Cooler Master have nailed the price. The Seasonic X-Series 650W KM3 retails for around £120 inc vat in the United Kingdom today. The Cooler Master V Series 700W which uses a very similar internal design from Seasonic is priced at £102.50 inc vat.

This is an exceptionally high value for money power supply and would be right at the top of our shortlist today.

Pros:

• Load regulation is superb.
• 80 Plus Gold+ efficiency levels.
• Pure modular design.
• 105c rated capacitors.
• can deliver almost 850W under load.
• great price point.

Cons:

• Still outside the budget for many people.

Kitguru says: A quality power supply with no weaknesses.

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