SAMA P1000 ATX 3.1 PSU Review – 1kW platinum power at a competitive price

1 - Introduction and technical data 2 - Unboxing, asccessory and cables 3 - Teardown, components, fan and protection circuits 4 - Cybenetics methods and equipment 5 - Performance and test results 6 - Operating noise 7 - Efficiency and power consumption 8 - Summary and conclusion

Efficiency and interpretation of the efficiency diagram

The efficiency diagram shows very clearly how the SAMA P1000 achieves its Platinum certification in practice and over which load range the power supply works particularly efficiently. The horizontal axis shows the power of the 12-volt rail up to 1000 watts, while the vertical axis shows the combined load of the 3.3 and 5-volt auxiliary lines up to 100 watts. The colored areas indicate efficiency classes, from light shades in the range below 80 percent to red for values above 94 percent. This makes it possible to see at a glance at which operating points the conversion efficiency is particularly high and where it decreases due to the design.

The center of the diagram is dominated by a large, closed red area, which roughly extends from around 300 to 600 watts of 12-volt power and is typically accompanied by secondary line loads of between 10 and 40 watts. Here, red stands for efficiencies of over 94 percent and marks the clear sweet spot of the platform. Many real-life scenarios lie precisely in this range, such as a gaming system with a powerful graphics card and moderately utilized CPU or a workstation that operates in the upper partial load range in productive applications. The fact that this range is so broad and closed shows how well the LLC topology with active PFC and DC-DC conversion is tuned. The average efficiency of 92.5 percent at 230 volts stated in the protocol is the average value across all load points; the efficiency peak in practice is therefore significantly higher, which is clearly demonstrated by the red area.

Around this core area there is a zone of darker and lighter shades of blue and gray, which represent efficiencies between around 90 and 94 percent. This region covers loads between approximately 200 and 300 watts and 600 to 750 watts. It shows that the power supply unit still works very efficiently outside the optimum range and does not only achieve its Platinum rating in a narrow window. For users, this means that both lighter gaming loads and more intensive workloads with higher utilization remain at a very high level of efficiency. Although the losses increase compared to the peak, they remain remarkably low in the context of a 1000 watt power supply unit.

In the low load range below around 100 to 150 watts, a much more colorful mix with green, yellow and violet segments is visible. Here the efficiency decreases due to the design, which is typical for practically all power supplies, as the fixed basic losses of the electronics are relatively more significant at very low power levels. However, the card also shows that despite these physical limits, the SAMA P1000 climbs into the 85% efficiency range from around 50 to 60 watts of 12-volt power and thus clearly sets itself apart from older or simpler platforms, which often perform significantly worse in the lower load range. In combination with the very low power consumption in standby mode and the ErP-compliant partial load values, this results in a well-rounded picture for typical office or idle scenarios in which the system only draws little power.

It is also interesting to look at the upper end of the performance diagram. In the region above around 800 watts of 12-volt power and high loads on the secondary lines, the colors change to lighter shades of blue and turquoise, which stand for efficiencies in the range of around 90 percent and below. This is normal for a power supply unit that is operating at the power limit and shows that the losses increase primarily due to the higher currents in the power components. It is important to note that there is no highly fragmented or patchy structure in this area, but a relatively even distribution. This indicates predictable behavior: The closer the power supply approaches the maximum load, the more clearly the efficiency decreases, but without unexpected dips. For real applications, this means that a good level of efficiency is still maintained even with a permanently high load, although the most energy-efficient operation is clearly in the medium load range.

The vertical structure also provides valuable information. The map shows that the load on 3.3 and 5 volt rails only has a moderate influence on efficiency as long as it remains within realistic limits. Only at very high secondary line loads in combination with extreme 12-volt outputs do the colors shift more visibly towards lower efficiency classes. As such operating points rarely occur in practice, typical configurations with several SSDs, fans and peripheral devices can be considered uncritical. The platform is clearly optimized to achieve its highest efficiency where modern systems draw the majority of their energy from 12 volts and the minor rails serve more as auxiliary rails.

Overall, the diagram clearly illustrates why Cybenetics has awarded the SAMA P1000 the ETA Platinum rating and why the device also achieves 80-Plus Platinum. The sweet spot is wide, the transition to higher and lower loads takes place without abrupt dips and the low load range is comparatively well under control for a 1000 watt power supply. For the target group, this means a noticeable reduction in waste heat, an easier job for the fan and therefore, in practice, quieter operation and lower energy costs over the service life of the system.

Efficiency measurement at increased ambient temperature

This efficiency diagram shows the measured efficiencies of the SAMA P1000 at different input voltages and in direct comparison to the requirements of EU Regulation 617/2013. It is striking that the measurements were carried out at a relatively high ambient temperature of 36 to 47 degrees Celsius, which is significantly more demanding than the standardized 23 to 25 degrees of many other tests. Under such conditions, a power supply unit naturally achieves lower efficiencies, which is why the values shown here place greater demands on the platform and paint a realistic picture of thermally stressed everyday operation.

The black curve represents the efficiency at 230 volts. It shows the typical curve of a modern LLC-based power supply unit, which is particularly efficient in the medium load range of around 30 to 60 percent. Efficiency rises rapidly from below 80 percent at very low loads to over 92 percent and a peak just above 94 percent. This peak confirms the Platinum rating in a power range that is central to practical use. From around 500 to 600 watts, the curve begins to drop slightly, but remains well above 90 percent up to full load, which is a strong performance given the high ambient temperature. The rather flat curve in the upper load range shows that the active PFC stage and the LLC resonance conversion work efficiently even under thermal load and that the losses in the power components remain limited.

The red curve shows operation at 115 volts, typically relevant for regions such as the USA or Japan. As expected, the efficiencies are somewhat lower here, as the lower input voltage means that higher currents flow and the losses increase, particularly in the PFC stage. Nevertheless, the curve is similarly structured: rapidly rising, flat plateau between 90 and 92 percent and a moderate drop in the upper load range. Even at just under 1000 watts, the efficiency still remains around 88 percent, which is a solid result for the electrical load at 115 volts. In conjunction with the ambient temperature, it can be seen that the platform works robustly and does not exhibit any sensitive dips.

The blue curve shows the requirements in accordance with EU Regulation 617/2013, which is relevant for energy efficiency control in idle mode and under partial and full load. It is interesting to note that the SAMA P1000 is well above the required values even under these adverse test conditions. While the EU curve remains clearly below 85 percent and drops even further in the lower partial load range, the 230-volt output of the power supply unit is consistently above this level, which underlines the efficiency reserves of the platform. Especially in the high load range, the gap to the EU standard is significant, which shows that the power supply offers far more than the minimum requirements for energy efficiency certifications.

The three curves together show that the SAMA P1000 is very well prepared for real thermal loads. The efficiency does not drop abruptly, but remains predictable over the entire range and without significant instabilities. Systems that are heavily loaded or operate in warm environments can therefore count on consistently good efficiency. At the same time, the power supply benefits from a well-balanced LLC topology, high-quality primary capacitors and a clean PFC stage, which ensures that the curves run smoothly. The diagram thus demonstrates that the SAMA P1000 not only achieves its Platinum certification under ideal conditions, but also delivers impressively stable efficiency even at high temperatures. This confirms the device’s claim to be a sophisticated and technically mature power supply unit for high-performance systems that does not lose its performance even under unfavorable conditions.

Efficiency of the 5-volt standby rail

The 5VSB rail (5-volt standby) is a central component of every ATX power supply because it remains active even when the PC is switched off. For example, it supplies USB charging functions, wake-on-LAN mechanisms or mainboard sensors. High efficiency in this area has a direct impact on idle and standby energy consumption, which is relevant both for ErP regulation and for real power consumption in everyday life. It is therefore worth taking a closer look at the diagram, which shows the efficiency of the 5VSB rail at input voltages of 115 volts and 230 volts.

The curve shows typical characteristics of modern flyback-based standby converters, which now achieve high efficiency levels thanks to optimizations such as SR MOSFETs and improved control controllers. The red curve represents operation at 115 volts, the black curve at 230 volts. Both have the same basic shape: a rapid increase from the low partial load range, a clear efficiency peak and a slightly decreasing curve at higher loads.

At 115 volts, the efficiency rises very quickly in the range just above one watt and reaches values of around 80 percent early on. The peak is around 80 to 81 percent in the load range between around 3 and 6 watts and then drops moderately, but remains in a range of around 79 percent up to around 10 watts. This is a good result, as efficiency losses are often greater at 115 volts in particular. The curve shows that the standby converter also works effectively at low mains voltages.

The 230 volt curve is somewhat weaker in the lower range, as it starts from a lower starting point at 0 watts and only rises to 77 to 79 percent in the 3 to 4 watt range. This is typical for higher input voltages because the losses of the primary switching stage are more significant in this range. Nevertheless, from around 5 watts the curve reaches very similar values to the 115 volt measurement and remains stable at around 79 percent, which is a good value for a 5VSB design. The slight drop in the range above 10 watts is technically normal, as the losses of the secondary rectification dominate at higher currents.

The comparison of both curves shows that the standby design of the SAMA P1000 has been cleanly tuned. The efficiencies are close to or just above 80 percent over large parts of the practical load range. This is clearly above older designs, which often only achieve 65 to 75 percent, and corresponds to a modern implementation, as is to be expected with high-quality power supply units. Especially in the context of the very low measured standby power consumption of 0.1338 watts under 230 volts, it is confirmed that not only the efficiency, but also the absolute power consumption in idle mode has been excellently optimized.

In summary, the diagram shows that the SAMA P1000 also operates efficiently and in accordance with standards in standby mode. The 5VSB rail achieves good efficiency levels across the entire relevant power range and makes a significant contribution to the power supply unit easily meeting the ErP Lot 3 and Lot 6 requirements. This places it technically above the average in its price class and shows that the platform is not only convincing under load, but also in energy-saving mode.

Power consumption in idle state (Vampire Power)

Vampire Power

The so-called vampire power describes the power consumption of the power supply unit when the computer is switched off, i.e. in standby mode, in which only the 5VSB rail remains active. This value is relevant for regulatory purposes, as it is directly incorporated into the energy efficiency specifications of ErP Lot 3 and Lot 6. At the same time, it is an indicator of how well the standby converter is designed and how efficiently internal losses are minimized. The SAMA P1000 shows a very good result here. The measured power consumption in standby mode is just 0.1338 watts at 230 volts. This value is well below the EU specifications, which allow a maximum of 0.5 watts for modern systems, and is even lower than many premium devices, which typically use between 0.15 and 0.25 watts. This makes the P1000 one of the more economical power supply units in its class.

The very low consumption shows that the standby converter is efficiently designed and that both primary and secondary losses have been effectively reduced. This applies in particular to the choice of controller, the optimization of switching frequencies in idle mode and the reduction of stray and leakage currents in the standby path. The fact that the power supply unit keeps this value stable even at elevated ambient temperatures confirms the thermal robustness of the design.

In practice, the low vampire power means that the power supply unit hardly contributes to the electricity bill over its entire service life if the system remains switched off. This efficiency can have a particularly positive effect in households or offices where PCs are left idle for long periods. At the same time, the result shows that the power supply unit easily meets the requirements of the European energy efficiency directives and is therefore also suitable for systems that have to meet strict regulatory requirements. Here, the very low vampire power speaks for a modern and efficiently designed standby architecture, which further rounds off the profile of the SAMA P1000 as a technically convincing power supply unit.

ErP Lot 6 / Lot 3 – specifications and classification

ErP Lot 6 defines the requirements for the energy efficiency of electronic devices when they are switched off or in standby mode and ensures that modern systems consume as little power as possible when they are not actively in use. For PC power supplies, this means that the power consumption in the soft-off state (S5), in which only the 5VSB rail remains active, must be particularly low. The regulatory limit is a maximum of 0.5 watts, although many manufacturers try to significantly undercut this value in order to create both normative reserves and to reduce real energy consumption.

The SAMA P1000 not only meets these requirements, but falls well below them. With a measured power consumption of just 0.1338 watts at 230 volts, the power supply unit is well below the ErP Lot 6 limit, demonstrating that the standby converter has been designed to be extremely efficient. In combination with the good 5VSB efficiency curve, a consistent picture emerges: the device is designed to consume as little energy as possible even when not in active operation.

ErP Lot 6 is particularly important in Europe, as systems without this conformity may not be placed on the market. For the user, the very low standby power consumption of the SAMA P1000 means that long-term power consumption remains minimal, even if the PC is frequently switched off but plugged in. This is particularly relevant for workstations with Wake-on-LAN or USB charging functions, which regularly use the 5VSB rail. The power supply unit thus demonstrates that it not only meets the regulatory requirements, but exceeds them by a wide margin. This makes it easily suitable for energy-efficient systems and modern EU-compliant PC configurations and once again confirms the good balance between efficiency design and practical standby behavior.