Fractal Design Integra R2 750W PSU Review Introduction

A little while ago we had our first encounter with Fractal Design’s power supply units, in our review of the Tesla R2 650W. The 80Plus Gold certified Tesla R2 proved to be a formidable adversary for the competition; however, the retail price is placing it out of the reach of most mainstream users. Today we will be having a look at the most powerful PSU of the Integra series, the 80Plus Bronze certified series of Fractal Design, the Integra R2 750W.

The Integra R2 750W is visually very similar to the Tesla R2 650W which we have already reviewed. However, it is less efficient, has fewer features and, even though it is more powerful, the 750W version currently retails for $89.99 incl. shipping. The 650W version retails for $20 less, at $69.99 incl.  shipping, which is nearly half the price of the equivalent Tesla R2 650W model that currently retails for $112.90 shipped. Fractal Design created this power supply series for medium-performance gaming computers and workstations with entry-level price points. The value of the Integra R2 series is undeniably much higher but how much performance has been sacrificed in the process? We will find out in this review.

 Fractal Design Integra R2 PSU Lineup:


Fractal Design Integra R2 750W

Fractal Design Integra R2 750W major features and specifications

 DC Total Power Output






3.3V and 5V combined








5V Standby (+5Vsb)


Packaging and bundle

 The box

The Integra R2 750W arrived in a small, cubic cardboard box, which resembles the packaging of a CPU cooler. The box appeared so small that we initially thought that we received a SFX power supply instead. Nevertheless, the small box hides a full size ATX power supply unit; it lacks however any real protection between it and the walls of the box.


In an effort to minimize the cost, Fractal Design kept the bundle down to a bare minimum. Inside the box we only found an AC power cable, black mounting screws, a user’s manual and only three short cable ties.


External Design of the Fractal Design Integra R2 750W

 Fractal Design Integra R2 750W

The chassis of the Integra R2 750W power supply shares the same base design as that of the Tesla R2 650W unit that we have already reviewed, having beveled edges and an integrated honeycomb fan guard as its prime aesthetic characteristics. However, the Integra R2 750W power supply is much shorter; at only 140mm deep, it most likely is the shortest 750W power supply currently available.

  Left Side Right Side

Rather than using stickers, Fractal Design painted the table with the electrical specifications and certifications of the Integra R2 on the right side of the unit. On the left side of the unit, the company logo and the power rating of the power supply has been sprayed onto the chassis.

 Top side

The crest of Fractal Design, a snowflake star, is embossed on the top side of the chassis.

 Front Side

The front side of the power supply is uninteresting; a honeycomb mesh is covering most of the surface and only an AC plug and the standard on/off switch are present.

 Rear side

Same as the Tesla R2 series, the rear of the power supply is plain and uninteresting, with only a narrow honeycomb vent being of notable importance. 


The Interior of the Fractal Design Integra R2 750W

 Cooling Fan

Even though the exterior of the Integra R2 is very similar to the Tesla R2, the inside is nothing like it. The changes begin with the cooling fan, which still has milk white blades but is now supplied by Hong Sheng, a Taiwanese manufacturer. The 120mm fan has a sleeve bearing and a maximum speed of 1900RPM.

 Interior View

The base design of the Fractal Design Integra R2 750W power supply is, obviously, entirely different than that of the Tesla R2’s. Even the OEM differs, as the Integra R2 750W has been obviously based on a HEC/Compucase design, unlike the Tesla R2 which is made by ATNG. HEC is a more popular OEM when it comes to middle/value range products and they do a great assembly/soldering job, yet their designs are simple and not usually capable of amazing performance.

 Filtering Stage

The filtering stage begins on the back of the AC receptacle and continues on the main PCB. A total of four Y capacitors, two X capacitors, three filtering chokes and a MOV compile a very good, complete filtering stage.

 Primary Stage

A large choke and a single Teapo 400V/470uF capacitor are the passive components of the APFC stage. The active components, a diode and three transistors, are on the heatsink near the edge of the unit, alongside with the main bridge rectifier. Two transistors on the heatsink next to the main transformer create the primary side of this power supply.

 Secondary stage

The heatsink on the secondary side of the transformer holds the six switches which convert the input to the DC lines, all of which are passive. Four generate the 12V line, one the 5V line and one the 3.3V line. This is the major technological difference between this unit and the Tesla R2, as the latter is using active switches (MOSFETs) and DC to DC converters, which tremendously boost the efficiency of a power supply. All of the secondary side capacitors are supplied by Teapo as well.

Test Setup

The load

In order to be able to effectively and efficiently test any computer power supply unit, we developed and constructed our own proprietary testing station. Our testing station consists of a number of power resistors and small capacitors, which in turn are connected to a RS485 electronic relay array which allow our load to be controlled through computer software alone.

USB interface and connection panel

When accuracy and speed are of critical importance, a simple multimeter or voltage meter is not sufficient for the task. To ensure the quality of our testing, an USB laboratory interface is being used to continuously monitor and record the readings of all voltage lines simultaneously. For ripple measurements, an oscilloscope is necessary and we chose the USB Instruments Stingray, the most widely used oscilloscope amongst low voltage PSU engineers and testers.

Measurement instruments

For accurate testing and repeatable results, a stable power input is also required. Thus, we are providing power to our test samples through a 3kVA VARIAC which allows us to control the input voltage of our test samples and also perform efficiency tests under both 110V AC and 230V AC input. A Lutron DW-6091 is also being used, monitoring the input voltage, real and apparent power, power factor and amperage.

The software

A power supply testing procedure would not be complete without thermal and acoustics tests. For our acoustics tests we are using a SL-5868P digital sound level meter, placed 1 meter away from the unit (DIN standard). Two PT100 sensors and their respective displays are being used to monitor the ambient temperature and the exhaust temperature of the unit.

Complete test setup during trial run


Testing results (Regulation & Ripple)





 Surprisingly, the electrical performance of the Integra R2 750W power supply was better than that of the Tesla R2. Voltage regulation results were about the same, with all of the voltage lines displaying a variation of about 2.4% between minimum and maximum load. The filtering however is significantly better, with the 12V line displaying a maximum ripple of 54mV at maximum load and the 3.3V/5V lines develop a maximum voltage ripple of about 26mV each. These are very good performance figures, less than half the maximum recommended values.

Testing results (Efficiency, Noise & Thermal)


Fractal Design appears to have optimized the Integra R2 750W for very high efficiency at low loads, as the power supply displayed amazing (87.2% with 230VAC) efficiency at 20% load for an 80Plus Bronze certified product. However, the efficiency of the power supply diminishes rapidly when it is heavily loaded, forbidding it from achieving a better 80Plus certification.


The Integra R2 750W is not a quiet power supply but it actually performs very well for an 80Plus Bronze certified power supply with such a small chassis and high power output. Noise levels are very low up to 40% load, with the unit being essentially silent. Between 40% and 60% load, the fan is audible but volume levels remain low, comfortable for everyday use. If a load of 400W or greater is placed on the unit, the fan will accelerate quickly, reaching clearly audible levels from a meter away.


The thermal performance of the Integra R2 750W was expected, all things considered. The 80Plus Bronze certified unit has a linear, steady thermal performance, with a temperature delta of 4.5 degrees Celsius at minimum load and 8.4 degrees Celsius at maximum load.

Fractal Design Integra R2 750W PSU Review Conclusion

 Today we had a look at the Integra R2 PSU series from Fractal Design, the least expensive and most basic series that they offer; although we are not certain that they realize that. Compared to the Tesla R2 650W, the 80Plus Gold certified model which we reviewed a little while ago and retails for $113 shipped, double the price of the equivalent Integra R2 model, the Integra R2 series suddenly looks as a much more appealing option.

Quality wise, the Integra R2 750W is very well made for a sub-$100 power supply. Yes, Teapo is not the favorite capacitor manufacturer of enthusiasts, neither HEC their preferred OEM; however, HEC did a great job designing and building a mainstream 750W power supply which can be bought for $89.99 incl. shipping, which Fractal Design covers with a 3-year long warranty.

Fan view

The performance of the Integra R2 750W power supply is not setting any records. Fractal Design clearly optimized this power supply towards electrical performance and it does deliver, with very good filtering and regulation on all voltage lines. Enhancing the efficiency at low loads was very clever as well, since a 750W unit will most likely spend >90% of its lifetime at sub-50% load levels. However, the small chassis and high capacity have a negative impact on the thermal performance of the Integra R2 750W unit, which stresses its cooling fan. At higher loads the fan does become noisy; however, such power levels denote the use of powerful GFX cards and it is extremely unlikely that a gamer would even notice the humming noise of a fan.

When comparing the Tesla R2 to the Integra R2, the latter is capable of better electrical performance, shares the same exceptional aesthetic design and the same 3 year old warranty. Of course, no one can claim that the Integra R2 is technologically on the same level as the Tesla R2, as the latter has a significantly more sophisticated design which offers increased efficiency, lower running temperatures and better acoustics. On the other hand however, the Integra R2 is capable of equal electrical performance for half the price tag.

Integra R2 750W

Legit Bottom Line:  The Fractal Design Integra R2 750W offers good quality, great electrical performance and is visually attractive for just $89.99 shipped. If value is your primary concern, then the Integra R2 750W definitely is quite a deal.