XPG Core Reactor II VE 850W PSU Review | Tom's Hardware

The XPG Core Reactor II VE 850W is a decent power supply with impressive efficiency and solid build quality. However, it falters under high temperatures and heavy loads, leading to excessive noise and reduced performance. It's ideal for mainstream users but not when continuous stress in a hot environment is expected.

Good voltage regulation

Fully modular design

Affordable price

7-year warranty

ATX 3.1 compliant

Mediocre ripple suppression

Noise under load

Thermal performance

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In 2022, Intel launched its significantly revised ATX v3.0 power supply standard, and with it, the 600 Watt-capable 12VHPWR cable to power video cards and other high-drain add-in cards. The release of the standard came with a lot of fanfare and excitement – the industry was preparing for a future where even flagship video cards could go back to being powered by a single cable – but shortly after, things became exciting again for all the wrong reasons.

The new 12VHPWR connector proved to be less forgiving of poor connections between cables and devices than envisioned. With hundreds of watts flowing through the relatively small pins – and critically, insufficient means to detect a poor connection – a bad connection could result in a thermal runaway scenario, i.e. a melted connector. And while the issue was an edge case overall, affecting a fraction of a fraction of systems, even a fraction is too much when you're starting from millions of PCs, never mind the unhappy customers with broken video cards.

So, the PC industry is taking a mulligan on the matter, quickly revising the ATX specification and the 12VHPWR connector to fix their design flaws. In its place we have the new ATX v.3.1 power supply specification, as well as the associated 12V-2×6 connector, the combination of which are intended to serve the same goals, but with far less of a chance of errant electricity causing damage.

Ultimately, the combination of the two new standards has required backwards-compatible changes on both the device (video card) side, as well as the power supply side. And as a result, power supply manufacturers are now in the process of releasing ATX v3.1-compliant PSUs that implement these revisions. For PSU vendors, the changes are relatively trivial overall, but they are nonetheless important changes that for multiple reasons, they are making sure to promote.

Getting down to business, the first ATX v3.1 power supply to enter our testing labs comes from ADATA sub-brand XPG, a prolific player in the PSU market. XPG recently expanded its product lineup with the introduction of the Core Reactor II VE series, the company's first foray into ATX 3.1-compliant PSUs. As a direct successor of the Core Reactor II series, the Core Reactor II VE is a relatively simple 80Plus Gold unit that distinguishes itself with its straightforward design, aimed at providing steady performance and taking on the best PSUs in the market.

In today’s review, we are taking a look at the 850W version of the Core Reactor II VE series, which is, for the time being, the most powerful ATX 3.1 unit XPG offers.

The XPG Core Reactor II VE 850W PSU features robust and visually appealing packaging. The box, made from durable cardboard, is adorned in a vivid red color and prominently showcases an image of the unit on the front. To ensure the PSU is well-protected during transport, it is securely encased in dense packaging foam.

The bundle is straightforward, containing just essential components such as mounting screws and the necessary AC power cable. Additionally, it includes several decorative stickers to add a touch of personalization.

This PSU features a fully modular design, which enables the removal of all DC power cables, including the 24-pin ATX connector. The cables are uniformly black, from their connectors to the wires, and are designed without sleeving, resulting in a consistent visual aesthetic.

The XPG Core Reactor II VE 850W PSU is encased in a chassis that measures 86 mm × 150 mm × 140 mm (H × W × D), aligning with the standard ATX dimensions. This relatively compact size enables the power supply unit to fit seamlessly into most tower PC cases. XPG’s engineers were forced to use a 120 mm fan for cooling, as a larger fan does not fit in such a small chassis.

Opting for a subtle aesthetic, the Core Reactor II VE 850W PSU features a sleek matte black finish. The design maintains a refined appearance, enhanced by embossed geometric patterns on the sides and an abstract geometric fan cutout that adds visual interest. The top of the unit displays a detailed sticker that provides its electrical specifications and certifications.

The front side of the XPG Core Reactor II VE 850W PSU hosts only the standard on/off switch and AC receptacle. The modular cable connectors are neatly organized on the rear of the unit, facilitating easy and mistake-free connections. Although the connectors are not color-coded, they are enclosed by a clearly printed, bright white legend on the chassis, which assists in precise cable installation.

The XPG Core Reactor II VE 850W PSU is equipped with a Hong Hua HA1225H12F-Z 120 mm fan, which includes an FDB (Fluid Dynamic Bearing) engine. This type of fan is favored by manufacturers of high-quality PSUs. The fan in this model can reach a maximum speed of 2200 RPM, an impressive figure for a 120 mm fan. The manufacturer’s website states that there should be a 2400 RPM fan installed but that probably was a typographic error.

The XPG Core Reactor II VE 850W ATX 3.1 PSU is manufactured by Channel-Well Technologies (CWT), a renowned OEM known for its capability in producing mid to high power output PC power supplies. CWT’s reputation as a respected OEM is firmly established, with their platforms being integral to some of the most popular power supply units on the market. We can also see that the same exact platform was used for the Core Reactor II 850W ATX 3.0 PSU, verifying that the difference between the ATX 3.0 and ATX 3.1 standards are very subtle, primarily reduced to the length of the PCI-Express 5.0 connector sense pins and their configuration. If anything, the quality went down a bit compared to the ATX 3.0 version of the series, as we can see that higher quality passive components were being used.

The Core Reactor II VE 850W PSU employs well-established topologies, ensuring reliable performance without unexpected deviations. The input stage of the power supply features a more robust transient filter than the ATX design guide baseline, equipped with four Y capacitors, two X capacitors, but just one filtering inductor, followed by two bridge rectifiers on their dedicated heatsink. A copper sheet shields the filtering stage from the rest of the unit. The Active Power Factor Correction (APFC) circuit active components lie on the primary heatsink along the edge of the PCB. The active APFC components are two 33N60M2 MOSFETs and a diode, along with a filtering inductor and a massive 400V/680μF capacitor from Elite.

In the primary inversion stage, the Core Reactor II VE 850W PSU utilizes a half-bridge LLC topology with main switchers (25N60EFL) mounted on a dedicated heatsink, a typical setup in contemporary power supplies for its cost-effectiveness and reliability. The secondary stage conversion features eight OnSemi NTMFS5C430N transistors on a vertical daughterboard, delivering a single 12V output. The 3.3V and 5V rails are managed by DC-to-DC conversion circuits on another daughterboard.

On the secondary side, the PSU incorporates a mix of both electrolytic and solid-state capacitors from Elite and CapXon, both of which are known but are not considered to be amongst the most premium capacitor manufacturers. The ATX 3.0 version of the series featured capacitors from Japanese manufacturers instead.

For the testing of PSUs, we are using high precision electronic loads with a maximum power draw of 2700 Watts, a Rigol DS5042M 40 MHz oscilloscope, an Extech 380803 power analyzer, two high precision UNI-T UT-325 digital thermometers, an Extech HD600 SPL meter, a self-designed hotbox and various other bits and parts.

The XPG Core Reactor II VE 850W PSU surpasses the requirements set by the 80Plus Gold certification with impressive margins. When operating with a 115 VAC input, this PSU demonstrates an average nominal load efficiency of 90.9% across a range from 20% to 100% of its capacity, which further increases to 91.7% with a 230 VAC input. The efficiency peaks at a load slightly less than half its maximum capacity. Low load efficiency is excellent, notably superior to that of many other units with a similar power output.

The XPG Core Reactor II VE 850W PSU does not have a "hybrid" fan mode - its fan is operational at all times. Even in ambient room temperature, the fan operates continuously but at very low speeds while the load is low, gradually increasing its speed as the load escalates beyond 500 Watts. This simplistic approach reduces the complexity of the design a little and the PSU virtually remains inaudible while the load is very low.

During its hot testing phase, the XPG Core Reactor II VE 850W PSU exhibits a marked decrease in efficiency under heavy loads, with figures dropping to 88.9% under a 115 VAC input and 89.7% with a 230 VAC source, compared to 90.9% and 91.7%, respectively, during cold testing. This significant decline is accentuated at higher load levels and is accompanied by signs of significant thermal stress. Although this PSU is rated for operation at an ambient temperature of up to 40°C, the effect that higher ambient temperatures had on its performance are rather severe.

In hot testing conditions, the fan of the XPG Core Reactor II VE 850W PSU operates continuously, at higher speeds than with a low ambient temperature and further increasing its speed as the load surpasses 400 Watts. It also nears its maximum speed as it approaches 80% capacity. This operational characteristic keeps the PSU relatively tolerable up to 60-65% load. However, beyond that point, the noise level rises significantly, making the unit audibly noticeable.

With its 120 mm fan, the XPG Core Reactor II VE 850W PSU effectively handles cooling, but temperatures do become uncomfortably high when the load exceeds 75%. Despite this increase, the temperatures remain below the threshold necessary to trigger the over-temperature protection (OTP). The designer seems to have made a major effort in balancing acoustics and thermal performance/reliability.

The electrical performance of the XPG Core Reactor II VE 850W PSU is competent, with effective voltage regulation across its outputs. However, ripple suppression on the 3.3V and 5V lines shows room for improvement, characterized as mediocre compared to industry leaders. The 12V rail exhibits a maximum ripple of 56 mV, and the ripple on the 5V and 3.3V lines measures at 38 mV and 34 mV respectively, indicating less stringent control compared to some high-end models. Despite this, the PSU maintains stable operation and matches the performance ratings advertised by the manufacturer.

During our thorough assessment, we evaluate the essential protection features of every power supply unit we review, including Over Current Protection (OCP), Over Voltage Protection (OVP), Over Power Protection (OPP), and Short Circuit Protection (SCP). The XPG Core Reactor II VE 850W PSU passed all critical protection tests, proving its capability to safeguard against scenarios that could compromise the PSU or connected components. The unit showed slightly loosely calibrated Over Current Protection (OCP) for the 3.3V and 5V rails, activating at 136% and 138% respectively, which is high but remains within acceptable limits. The 12V rail’s OCP activation at 146% is extremely high but we are not surprised considering the need of manufacturers to comply with the power excursion design guide requirements.

The XPG Core Reactor II VE 850W PSU distinguishes itself as the first ATX 3.1-compliant unit from XPG, setting a benchmark in the power supply landscape with its adherence to the latest standards. Priced at an MSRP of $119 and likely to retail for significantly less, this power supply unit blends high-quality performance, robust construction, and a price point that appeals to a broad spectrum of users. Manufactured by the reputable Channel-Well Technologies, the unit benefits from expert craftsmanship, enhancing its durability and ensuring it stands up to the rigors of daily use. The provision of a 7-year warranty by XPG further emphasizes their confidence in the PSU's long-term reliability.

In terms of performance, the XPG Core Reactor II VE 850W does very well, achieving impressive efficiency ratings that greatly exceed the requirements for 80Plus Gold certification, recording average nominal load efficiencies of 90.9% on 115 VAC and 91.7% on 230 VAC. Power quality is great too, with fantastic voltage regulation on all lines and good filtering on the primary 12V line. Despite its strengths, it is worth mentioning that the unit does exhibit only moderate ripple suppression on the 3.3V and 5V lines, which may be adequate but not on par with other high tier products.

Thermal management in the Core Reactor II VE is acceptable, mostly thanks to its powerful 120 mm fan, which effectively dissipates heat across varying loads. However, the unit's electrical performance does show signs of degradation under extreme conditions due to thermal stress, particularly when operating near full capacity in higher ambient temperatures. This aspect is crucial for users to consider, especially those in warmer climates or with high-load applications, as it impacts both performance and noise levels, with the latter increasing significantly under heavy loads.

The XPG Core Reactor II VE 850W PSU is a significant release, being the first to meet ATX 3.1 specifications, seemingly offering forward-looking compatibility with next-generation hardware. The balance of cost, capabilities, and the extended warranty make it an attractive option for a wide range of users, from gamers to professional workstation builders. While it performs admirably across most parameters, potential buyers should weigh the implications of its poor performance under adverse operating conditions. Still, its performance metrics under typical operating conditions and quality make it a worthy investment for those who want a balanced product that does not break the bank.

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Dr. E. Fylladitakis has been passionate about PCs since the 8088 era, beginning his PC gaming journey with classics like Metal Mutant and Battle Chess. Not long after, he built his first PC, a 486, and has been an enthusiast ever since. In the early 2000’s, he delved deeply into overclocking Duron and Pentium 4 processors, liquid cooling, and phase-change cooling technologies. While he has an extensive and broad engineering education, Dr. Fylladitakis specializes in electrical and energy engineering, with numerous articles published in scientific journals, some contributing to novel cooling technologies and power electronics. He has been a hardware reviewer at AnandTech for nearly a decade. Outside of his professional pursuits, he enjoys immersing himself in a good philosophy book and unwinding through PC games.

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