Comparison Deepcool PN-D PN850D vs Deepcool PM-D PM850D

A standard for power supplies that supplements the ATX specifications regarding power supply along the 12 V line. Introduced into use since the time of the Intel Pentium 4 processor. In the first series of the standard, the +5 V line was mainly used; from version 2.0, the +12 V line was introduced to fully power the components computer. Also in the second generation, a 24-pin power connector appeared, used in most modern motherboards.

The number of SATA power connectors provided in the PSU.

Nowadays, SATA is the standard interface for connecting internal hard drives, and it is also found in other types of drives (SSD, SSHD, etc.). Such an interface consists of a data connector connected to the motherboard, and a power connector connected to the PSU. Accordingly, in this paragraph we are talking about the number of SATA power plugs provided in the PSU. This number corresponds to the number of SATA drives that can be simultaneously powered from this model.

The number of Molex (IDE) connectors provided in the design of the power supply.

Initially, such a connector was intended to power peripherals for the IDE interface, primarily hard drives. And although the IDE itself is completely obsolete today and is not used in new components, however, the Molex power connector continues to be installed in power supplies, and almost without fail. Almost any modern PSU has at least 1 – 2 of these connectors, and in high-end models this number can be 7 or more. This situation is due to the fact that Molex IDE is a fairly universal standard, and with the help of the simplest adapters, components with a different power interface can be powered from it. For example, there are Molex - SATA adapters for drives, Molex - 6 pin for video cards, etc.

The 16-pin PCIe power connector is designed to replace the existing 8-pin counterparts. It consists of twelve lines for current supply and four more for data transmission. The connector provides up to 600 watts of additional power, which is a fourfold increase in power compared to the 8-pin versions of the interface. Additional PCIe connectors of all formats are used to power those types of internal peripherals that no longer have enough with the 75 watts delivered directly through the PCIe slot on the motherboard.

Protection schemes provided in the power supply unit. In addition to the aforementioned OVP (Over Voltage Protection), OPP (Over Power Protection), and SCP (Short Circuit Protection), modern PSUs may include the following safety functions:

— OCP. OCP in power supplies monitors the current on power lines and shuts down the PSU if consumption becomes dangerously high, to prevent overheating wires, connectors, and power elements inside the unit, and to avoid affecting components. Unlike OPP, which triggers based on the total power of the whole unit, OCP often catches a localized issue on a specific line or group of outputs. Compared to SCP, it's an "earlier" protection: it reacts before a full short circuit forms when resistance is not zero but current is already risky. Real-life examples include an unsuccessful graphics card overclock, a damaged GPU power cable, or the rare but unpleasant case of connector bending/melting: OCP will shut down the unit faster than you'll notice the smell of plastic.

— UVP. UVP monitors the voltage drop on the power supply's outputs and shuts it down when the values become too low for stable operation to avoid freezes, data writing errors, and "half-dead" modes, which are especially unpleasant for the motherboard and drives. Paired with OVP, these protections work like "frames": OVP catches dangerous spikes, UVP catches dangerous drops, while SIP often tries to smooth out the power issue at the input. A typical ex...ample would be an overloaded weak PSU, poor grid, or turning on powerful appliances at home: instead of unstable operation and strange reboots, UVP prefers to shut down the system predictably.

— OTP. OTP monitors the temperature inside the power supply and shuts it down when the heat becomes critical, protecting the transformer, power switches, and capacitors from accelerated wear and accidents. This is a "harsher" safety net than AFC: automatic fan control tries to prevent overheating, while OTP kicks in when cooling no longer suffices— for example, if the case is clogged with dust, the fan stops, the PSU is in a cramped compartment, or the PC runs under heavy load for a long time in summer. In real life, OTP often saves the day when a user inadvertently blocks the air intake or the fan starts failing: instead of smoke and component degradation, the unit simply turns off.

— SIP. SIP in power supplies is designed for "dirty" power conditions: transient surges, drops, and inrush currents that occur when a fridge compressor, pump, or air conditioner starts up at home, or when the network is unstable. Conceptually, it aligns closer to smoothing out input problems than to OVP/UVP, which already monitor the output and simply shut down the PSU at dangerous values; SIP aims to enhance system resilience to everyday voltage drops and spikes but does not replace a full external stabilizer or robust power protection if the grid is truly bad. A typical example would be a private house or old housing stock: SIP helps endure minor network "nudges" without sudden reboots.

— NLO (No-Load Operation). The ability of a power supply to correctly start and operate even with zero or very low load on the outputs, without "floating" voltages and instability. Unlike protections like OVP/OCP/SCP that respond to emergencies (overvoltage, overload, short circuit) and often shut down the PSU, NLO focuses on stability when consumption is minimal, or the load is temporarily absent, reducing the risk of odd malfunctions during testing or in energy-saving scenarios. In practice, NLO is useful when testing the unit on a bench without a connected PC, when the system starts with a minimal set of components, and when the computer spends most of the time idling, reducing consumption to a "trivial" level.

— AFC. AFC in power supplies manages fan speed based on temperature and load: it rotates slower and quieter when idle, and speeds up as consumption increases to dissipate heat in time. This is not "emergency" protection like OTP, which shuts down the unit during overheating, but a preventative measure: AFC helps maintain temperature at a normal level, thereby indirectly prolonging the lifespan of PSU components. A real-life example is that at night, in a quiet room, the PC doesn't hum under low load, and during gaming, the cooling automatically intensifies, preventing OTP from triggering.

Manufacturer's warranty provided for this model.

In fact, this is the minimum service life promised by the manufacturer, subject to the rules of operation. There are both models with a small warranty up to 3 years, and more advanced power supplies, in which the warranty can reach 7, 10 years and even 12 years. In general , a 5-year warranty(for example) does not mean that the device will fail after the specified time. Most often, the actual service life of the device is much longer than the guaranteed one.

Specific warranty periods may vary even for similar drives from the same manufacturer. So not