Evaluation of be quiet! Straight Power E7 CM 680W (80+ Bronze Certified)

be quiet! has made 2 revisions out of its own product line for the past 6 months,
respectively upgrading Straight Power Series into “Deluxe” version (coded as E6/non CM),
and upgrading Straight Power Series recently into CM version (coded as E7).
Therefore, you’ll find E6 and E7 versions of Straight Power series on the market.
The major difference between these two versions is whether it has CM or not.

be quiet! Straight Power E7 CM (Cable Management) has 3 wattages for you to choose from, 480, 580 and 680W.
This wattage range covers the wattage commonly required by most of the users.
In addition, all of them are 80Plus Bronze certified.

The efficiency test result of E7 680W’s 20/50/100% loading listed in 80Plus website is 85.84/86.86/83.05% respectively.
The test result looks quite satisfying. 80+ Bronze could be considered as an index of middle-high level power supplies.

Here is our start - Straight Power E7 CM 680W
There is no jaguar image as be quiet! usually would put on their color box this time.
Through the simpler color combination, the color box looks of even more quality.


Accessories
Multi-language User Manual, CM Cable Kit, Cable Tie, Screws, Power Cord


Straight Power E7 680W Dimensions 160mm X 150mm X 86mm
The case is coated in titanium gray, making it quite different from black cases commonly seen.


The sand texture surface of the case is finger-print proof and the appearance of the heat sink is also a great feature of the product.   


CM Cables
1 X 12V P8
2 X 6 Pin VGA
2 X 6+2 Pin VGA
8 X HDD
7 X SATA
2 X FDD




Connectors from inside of E7 680W
1 X 24/20 Pin
1 X 12V P4
2 X Fan connectors


12cm FDB fan with black symmetric grill-like fan guard is adopted into this series.
The fan guard does look like BBQ grill, ……anyway, quite a special design.
E7 series is integrated with a FDB fan, developed by be quiet!, which has a MTBF of 300,000 Hrs and a super low noise level down to 17dBA.


The rear end of the PSU is equipped with the commonly seen ventilation holes in honeycomb shape.
Active PFC, applicable in 110~240Vac


CM connection sockets
A sticker is pasted stating the name/function of each socket so that end users could avoid mistaken connections.
There are also 3 rows of ventilations holes beneath for enhancing overall cooling mechanism.



Spec of Straight Power E7 CM 680W; Model Name: BQT E7-CM-680W
+12V*4, with a combined current of 52A and a combined output wattage of 624W


Silient Wings, a FDB fan designed by be quiet!, is also specially integrated into E7 series.


The M/B used in this test is GIGABYTE P55A-UD5, a middle-high spec among LGA 1156 sockets.
Through my recent experience, I found out when LGA 1156 was under overclocking mode, it would demand quite a high consumption of +12V.


UD5 is integrated with USB3.0 and the latest MB technology.


Test Platform
CPU: Intel Core i7-870
MB: GIGABYTE P55A-UD5
DRAM: CORSAIR DOMINATOR-GT CMG4GX3M2A2000C8
VGA: GIGABYTE GTX260 OC SLI
HD: CORSAIR CMFSSD-128GBG2D RAID0
POWER: be quiet! Straight Power E7 CM 680W
Cooler: Tuniq Tower 120 Extreme
OS: Windows7 Ultimate 64bit


OS system defaults
CPU 200 X 20 => 4000Mhz
DARM DDR3 2000 CL8 8-8-24 1T


OCCT V3.1.0
POWER SUPPLY mode, Shader Complexity 8


What above is the test platform used in this test. In order to display the status of power consumption during the test,
the consumption data would be obtained from the measurement made by “Power Angle”.

Upon entering the desktop screen of OS system- 225~226W


Active PFC - 0.97~0.98


The test items for the Power Supply in OCCT
i7-870 OC 4GHz, a 4-core CPU with simulated full-loading 4-core HT and a physical speeding up from GTX260 - 681~727W。

Running power supply test item in OCCT
i7-870 OC 4GHz, quad physical cores and quad HT virtual cores run in full speed plus GTX260 SLI 2WAY and GTX260 PhysX - 681~727W



Active PFC - 0.99~1.00


The measurement data outputted by Power Angel is only for reference, since its accuracy level is not that high.
Though 3WAY SLI couldn’t be applied to reach an utmost 3D efficiency and hence put the system under a full loading condition during the test,
still, I got an utmost consumption value, 727W, from this test, which could also be considered as a middle/high loading test for 680W.

OCCT test result
CPU temperature fluctuation


System temperature fluctuation


CPU voltage fluctuation
While in standby mode, it was around 1.38V; during full-speed operation, it was around 1.38~1.41V.
The fluctuation range of CPU’s voltage is majorly related to the voltage characteristic of M/B.


3.3V
The utmost value measured was 3.34V; the fluctuation majorly lied in the range of 3.28~3.3V.
The fluctuation rate was around 1.80%.
3.3V


5V
It was around 4.95~5.03V. The fluctuation rate was around 1.59%.


12V
The utmost value measured was 12.48V, majorly covering the rage of 12.03~12.10V. The fluctuation rate was around 3.6%.  


The voltage fluctuation rates of Straight Power E7 680W’s 3.3V & 12V were both under 1.8%, which is considered quite a satisfying number.
The fluctuation of 12V started to become less stable after OCCT operated over 10 minutes.
The rate was around 3.6%, a larger fluctuation rate than any other voltages tested. However,
this fluctuation rate still lied inside the range of +-5% required by Intel.
Also, the voltage measured for 12V was not actually the real voltage value.

Here, we used a multimeter for a more accurate result.
While in standby mode, 5Vwas around 5.07V, still a bit higher than that measured by M/B.


While OCCT was operating at full-speed, 5V was around 5.07~5.0V, making almost no difference from that measured in standby mode.  


While in standby mode, 12 was around 12.13V, a bit lower than 12.43V measured by M/B.



While OCCT was operating at full speed,
12V was around 11.92~11.93V; 0,20V lower than it was in standby mode.


With the application of the multimeter, the voltage fluctuation of 5V at full speed was only 0.02V and 12V was only 0.20V.
Both of these two values were much better than those measured by M/B in OCCT operation.
Though the fluctuation rate of 12V in OCCT operation was 3.6%, it was actually only 1.60% measured by multimeter, apparently a lot better.

Conclusion:
Advantages:
1, the color box of Straight Power E7’s latest version is a lot more attractive
2, special case coating and fan guard design
3, 80Plus Bronze certified; equipped with APFC circuit
4, all capacitors are Japanese, and noise level is only 17dBA
5, 5-year warranty, free to exchange for a new one within 540days if malfunction happens, and free NG PSU collection and delivery within 3 years.

Disadvantages:
1, the fluctuation range of 12V still leaves room for improvement
2, it would be better if 12V is changed into single rail




Efficiency  ★★★★★★★★☆☆
Material    ★★★★★★★★☆☆
Spec.      ★★★★★★★★★☆
Appearance ★★★★★★★★★☆
C/P        ★★★★★★★★☆☆

Upon my first glance at Straight Power E7, I could tell it was quite a special product.
Its appearance and fan design both greatly differentiate it from other ordinary looking power supplies.
Also, in other points you could also see how hard be quiet! has tried to differentiate it from other PSU,
such as the external fan connectors that allows more silence for the system, honeycomb ventilation holes on both sides of the case, scratch-proof case,
and the rounding of case sharp corners that could prevent users from being hurt, etc.

During the system test, E7 CM 680W was very quiet in both standby and full-speed modes; hardly could you hear any noise.
The temperature measured from its surface was around 45~50℃.
The stability of 3.3V & 5V is relatively higher than that of 12V.
Though after voltage fluctuation of 12V was more accurately measured by a multimeter,
the fluctuation rate was proved 50% less than that measured by M/B, still there is room for improvement of 12V’s stability.

The market price range of be quiet! Straight Power E7 680W is around 5990NTD, roughly equal to 186USD,
making it neither an expensive nor an inexpensive PSU on the market.
Though the quality is good and the materials used are of high quality, personally, I think if the price could be lowered a bit, it would be even better.
At least, a lowered price would allow end users who are interested in this product more possibility to purchase this product. : )