EVGA 500B 500W Power Supply Review Introduction

 It appears that today every company wants a piece of the PSU market cake. Almost every large manufacturer of anything computer-related has been trying to diversify towards that segment of the market. EVGA, renowned as a GFX card maker, is no exception. Not too long ago they presented several high-performance units, aiming towards enthusiasts and overclockers.


Today we are having a look at their first attempt to enter the lower segments of the PSU market with a value-oriented product, the 500B. With a MSRP of $49.99 and a street price of $34.99 + shipping (after rebate), it appears to be quite a deal for the features that the company claims it offers. How about its quality and performance though? We will be putting those to the test in this review.

 EVGA 500B features and specifications

Apparently EVGA’s webpage could use some updating, as it appears to be promoting this unit as a “fully modular” model with “all-Japanese capacitors”, which is not true.


100-240 VAC, 15A, 50-60 Hz



















500W @ +50C

Unboxing the power supply

The box

 The box which the 500B is supplied in is sturdy and functional. The artistic theme is good, lacking however a good picture of the unit itself, which is not ideal for those browsing inside a physical shop.

The box (rear)

On the rear side of the box, one can find a few small pictures of the power supply, along with a thorough list of all its features and performance specifications. All information are in English only.

Bundled items

EVGA retails the 500B as a low-cost product and the bundle reflects that, as there is only a small manual, the AC power cable and four mounting screws.

External Design


Although this is a low-cost product, EVGA did try to make the appearance of the unit unique. The chassis has been sprayed with a matte black paint and, at 150 mm deep, it is fully ATX-compliant in terms of length. EVGA went with a proprietary fan grill, featuring a wide exterior ring and a metallic badge with the company logo at the center. The wattage of the power supply is printed right next to the fan.

Side stickers (right side)


Side stickers (left side)

Strangely, EVGA installed an identical large sticker, featuring the most important electrical specifications and certifications of the 500B power supply, on both the left and right side of the unit.

Rear Side

All of the cables of this power supply are hardwired to the chassis, leaving the rear side of the unit completely plain, with the exception of a few ventilation openings. EVGA is using simple color-coded wires, all sleeved with black sleeving.

Front Side

The front side of the EVGA 500B is entirely plain, with only the AC power plug and a simple on/off switch present.

A look inside


The cooling fan

A Heroichi (HEC) 120mm fan can be found beneath the fancy finger guard of the EVGA 500B. It is a simple, sleeve bearing fan with a maximum speed of 1800RPM.

Inside the EVGA 500B unit

The OEM behind the creation of the EVGA 500B Bronze is no other than the supplier of its cooling fan, Heroichi. The 500B is based on a quite popular design, used in several low-cost products, which is relatively basic but very effective. The build quality is not exceptional, yet it is excellent for a product of such a price range.

The filtering stage

A small PCB is attached on the rear of the AC receptacle and holds part of the filtering stage. The EVGA 500B has a total of four Y capacitors, two X capacitors, two chokes and a MOV installed, forming an effective transient filter.

Primary side

We can see the single rectification bridge right before the APFC circuit, on its own small dedicated heatsink. The APFC consists of a single CapXon 400V/270uF 85°C capacitor, a large filtering coil, two transistors and a diode. The active components of the APFC are attached onto the large heatsink next to the primary side of the main transformer, along with the primary inversion transistors. There are two transistors, forming a simple half-bridge inversion topology.

Secondary side

The secondary side is not very interesting, as this model is not using any “exotic” topology or feature. Four transistors are generating all of the voltage lines; two for the 12V line, one for the 5V line and one for the 3.3V line. However, the lines are group regulated, meaning that the 12V and 5V lines are sharing the same regulation pathway. All of the secondary side capacitors are supplied by Teapo.

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)

t v3 v5 v12

Although the electrical performance of the EVGA 500B is not by any means special, it is more than satisfactory for the price level of the power supply. Voltage regulation is at about 2% for the 12V and 5V lines, while the regulation of the 3.3V line is a little weaker, at nearly 3%. Ripple filtering is not on par with high-performance units but it certainly is more than satisfactory for a sub-$50 product, with the maximum ripple we recorded being 64mV at full load, almost half of the 120mV acceptable limit that the ATX design guide dictates.

Testing results (Efficiency, Noise & Thermal)


The EVGA 500B easily complies with the 80Plus Bronze efficiency certification when powered by either an 110VAC or a 230VAC voltage source. With a 230VAC input, it manages to reach a maximum efficiency of 85.8% at 50% load and the minimum efficiency is 82.7% at maximum load. Reducing the input to 110VAC has, as expected, a negative impact on the overall efficiency of the power supply, by about 0.9% across the entire load range.


Even though the EVGA 500B is quiet when lightly loaded, that can change quickly as the load increases. Even small changes in load can boost the speed of the cooling fan, which becomes audible once the load exceeds 50% of the unit’s capacity. We can expect this power supply to be rather quiet while performing simple everyday tasks, such as browsing or listening to music, yet clearly audible when the power drain increases significantly, such as from a good GFX card while gaming.


The thermal performance of the EVGA 500B is very linear to the load, just as the acoustics of the fan. At low load, the EVGA 500B should not even become warm to the touch. As the load increases, the temperatures keep rising, by about 0.75 °C per 10% load.

EVGA 500B 500W Power Supply Review Conclusion

When we set our eyes upon the EVGA 500B, we already knew that it was designed to present a high-value option to advanced users on a tight budget, not a product designed to please the most hardcore of enthusiasts, therefore our expectations regarding its quality and performance were rather low. EVGA managed to prove us wrong, demonstrating that a balance between performance, aesthetics and quality is very much possible even on a sub-$50 product.

Cooling fan finger guard

As far as quality is concerned, HEC is one of the most renowned designers when it comes to value-grade products for a reason. Their designs have been powering OEM and low-power home and office computers for decades now. As such, it was unsurprising that the EVGA 500B was one of the most well-made sub-$50 power supplies that we have ever seen. However, despite the excellent quality of the assembly, the components are of mediocre quality, as EVGA had to keep the overall cost of the unit down.

The EVGA 500B

Overall, the EVGA 500B delivers satisfactory performance on all fronts. The electrical performance of the power supply is very good, especially considering the price range of the product, it is efficient and has relatively low running temperatures. It also remains quiet while the load is low, allowing for peace of mind when performing low-intensity tasks. With a MSRP of $49.99 and a street price of $34.99 + shipping (after rebate), it does present tremendous value to advanced users under a tight budget.


Legit Bottom Line: If you are shopping for a low-cost PSU to power a single GFX card gaming PC, or a low-power home/office system, then the EVGA 500B should definitely be in your shortlist.