Cooler Master V850 SFX Gold

The Cooler Master V850 SFX Gold is an 850-watt, fully modular power supply in the compact SFX form factor. It belongs to the company's V SFX Gold series, which the manufacturer describes as bringing the quality of its V series into a size that fits mini-ITX systems. The product page labels it ATX 3.1 in its headline features, while the detailed specification table lists the SFX 12V version 3.42 design standard, and this page reports both statements as published. Unusually for the format, the box includes an SFX-to-ATX bracket, so the unit can also be installed in a normal ATX case. This page collects the published specification, explains what the numbers mean for a small-form-factor build and leaves out anything the manufacturer does not state.

Why SFX matters

SFX is a smaller power-supply standard than ATX. Cooler Master lists the dimensions of this unit as 100 by 125 by 63.5 millimetres, which is far smaller than a full-size ATX supply, and the reduction is what makes the unit fit in mini-ITX cases that have no room for anything larger. The manufacturer's own text explains that as demand for smaller systems has risen, builders struggled to find SFX power supplies from series and brands they trust, and presents this unit as its answer. If you are choosing between formats, our guide to SFX versus ATX power supplies explains the trade-offs in fan size, noise and capacity, and our overview of ATX, micro-ATX and mini-ITX case form factors helps you match the supply to the case.

Rated power and efficiency

The unit is rated at 850 W and sits in Cooler Master's above-750-watt category. It carries the 80 PLUS Gold certification, and the manufacturer states that this level means a guaranteed typical efficiency of 90 percent, with the specification table listing 90 percent at typical load. The page also lists an ETA Gold rating and a LAMBDA Standard+ rating, which are separate third-party noise and efficiency classifications, and compliance with ErP 2014 Lot 3. The input is 100 to 240 V at 50 to 60 Hz with a current of 12 to 6 A and active power-factor correction, so the supply works on both 115 V and 230 V mains. Cooler Master also stresses that efficiency describes only how well the unit moves power from the wall to your components and says nothing about reliability, a fair reminder that the label is one factor among several.

Fan and noise

The cooling fan is 92 mm with a fluid dynamic bearing, and the manufacturer points out that the main source of noise in a power supply is normally the fan. The argument made on the page is that a small size, high efficiency and good heat dissipation together keep the overall noise to a minimum. As a general rule, small fans of this size spin faster than large ones, so the noise of an SFX supply at high load is a genuine consideration in a quiet build. The page publishes no noise figure in decibels, so we do not quote one. The operating temperature range is 0 to 50 degrees Celsius.

Connectors and modular cabling

The cabling is fully modular, including the main 24-pin connector. The connector list on the specification page names one 24-pin ATX connector, one EPS 4+4-pin connector, one EPS 8-pin connector, four PCIe 6+2-pin connectors, eight SATA connectors and four 4-pin peripheral connectors. The page does not list a 12V-2x6 or 12VHPWR graphics connector, so a card that needs that connector would rely on an adapter, and you should check the box contents and the graphics card requirements before buying. The value of modular cabling in a small case is practical: you connect only the cables you need, which preserves space, improves airflow and makes the build look tidier. For more on that, see our guide to power supply wattage to size the unit against your components.

SFX-to-ATX bracket

The included bracket converts the unit's footprint to that of an ATX supply, which Cooler Master says makes this its first power supply usable from mini-ITX systems up to E-ATX motherboards. That is a helpful property if you might change cases in the future, or if you simply want a compact, quiet supply for a normal case. The company's slogan for the series is Make It Yours, and the near-universal case compatibility is the point it stresses.

Protections, hold-up time and standards

The specification table lists over-power, over-voltage, over-temperature, over-current, short-circuit and under-voltage protection, together with surge and inrush protection, and it lists regulatory marks including TUV, cTUVus, CE, BSMI, FCC, CCC, EAC, RCM, KCC, CB and UKCA. The power-good signal is specified at 100 to 500 milliseconds, the hold-up time at 16 milliseconds, which is how long the unit keeps its outputs stable after mains power is lost, and the mean time between failures at more than 100,000 hours. That last number is statistical, not a guarantee of lifetime. The model number is listed as MPY-8501-SFHAGV with a regional suffix.

Practical notes for a small build

Before buying any SFX supply, confirm that the case explicitly supports the SFX standard, or plan to use the included ATX bracket in a case that takes full-size supplies. Check the length of the graphics card and the routing space for the cables as well, because a compact case leaves little room to hide the connectors. The connector counts on the specification page give a useful starting point: four PCIe 6+2-pin connectors are enough for a graphics card with two 8-pin inputs plus spare, and the two EPS connectors, a 4+4-pin and an 8-pin, cover a high-end processor board that asks for two CPU power inputs. Since the page lists no dedicated 12V-2x6 cable, verify how your specific card is powered before you order.

Two specification lines deserve a plain-language explanation. The power-good signal, listed at 100 to 500 milliseconds, is the short delay after switch-on before the supply tells the motherboard that its outputs are stable and it may start. The hold-up time, listed at 16 milliseconds, is the opposite case: how long the outputs stay within tolerance after the mains input drops out, giving the system a moment to ride through a brief interruption. Both are conventional design figures rather than features that change how you use the unit. Likewise, the mean time between failures above 100,000 hours describes a statistical model of a large batch of units, not the lifetime of the one on your desk; the ten-year warranty is the more practical measure of the manufacturer's confidence.

Warranty and positioning

All V SFX Gold models come with a ten-year warranty, which is generous for a compact unit and consistent with the manufacturer's statement that reduced size should not mean reduced quality. The natural alternative within the same brand is a full-size unit such as the V850 SFX Gold versus MWE Gold 850 V2 comparison, which trades the small size for a larger fan; you can also look at the Corsair RM850x page for another 850 W design, and browse the complete power supply category. This page states no price, so confirm price and stock with a retailer. None of the statements above is a test result; all values are the manufacturer's.

Product image: Cooler Master product image.