EVGA 650/550 GM SFX Power Supply Review: Tiny & Tenacious

One of the most impressive components used in our popular Sliger SM560 build guide was the extremely small yet capable SFX power supply unit, the EVGA SuperNOVA 550 GM and today we are reviewing both the EVGA 650 GM and 550 GM. We’ll show you not only how remarkably small they are but also how well they perform and the type of noise levels you can expect from EVGA’s latest SFX power supplies.

Unboxing & Overview

The outside of the box displays EVGA’s SuperNOVA GM branding as well as the 80 Plus Gold badge and the wattage of the unit.

evga sfx review

The back of each box displays key features such as a fully modular design, 100% Japanese capacitors, 92mm two-ball bearing fan and a generous 7-year warranty from EVGA.

evga supernova 650 gm review
The back of the EVGA 650 GM box.
evga supernova 550 gm review
The back of the EVGA 550 GM box.

Upon opening the box, we are greeting with the manual on the left side above the power supply and the included cables are neatly organized on the right side. Additionally, a power supply tester, an AC power cord and SFX to ATX bracket are included.

evga sfx 550

Cables include:

  • 1x 24 pin ATX
  • 1x 8 pin (4+4) EPS (CPU)
  • 2x 8 pin (6+2) PCIe
  • 1x SATA (550 GM) or 2x SATA (650 GM)
  • 1x Four-Pin Peripheral Cable
  • 1x Floppy Adapter
evga sfx power supply cables

Once the protective foam padding is removed, we are presented with the power supply.

evga sfx 650 review

The top of the unit displays EVGA’s tasteful, minimalistic logo. There’s also a sticker that has the part number, UPC, EAN and serial number of the unit.

evga 650w sfx review

The front of the unit is where all the ports are located.

evga sff power supply

The EVGA GM series are fully modular power supplies, making them an absolute godsend for the ITX builds they were made for as every ounce of space is precious. Plus, less cables means better air flow.

evga sfx power supply

The bottom of the unit shows of the wattage and here you can see the 92mm double ball bearing fan.

evga sfx psu

The back of the unit has the power port, an eco mode button and the main power switch. We’ll get to eco mode later.

evga eco mode

The back, with the sticker removed.

evga sfx gm

It’s difficult to grasp just how small a true SFX power supply is until you have one in your hands. Here is a comparison of the EVGA 650 GM and the Seasonic Prime Snow Silent 650W. Aisde from the fact that EVGA managed to pack 650 watts of power into this tiny little box, which is a feat in and of itself, look at how much smaller it is than the Seasonic!

sfx vs atx psu

Even more impressive is the fact that these pint-sized units are just as good as their larger ATX brethren. With the included ATX adapter, the GM series is compatible with nearly every case on the market, through ITX builders will certainly appreciate the 650/550 GM the most.

sfx vs atx psu size

Performance & Noise

Simply put, EVGA’s eco mode is amazing. We used the 550 GM in our Sliger SM560 build which is an ITX sized computer that sits on our desk next to the mouse/keyboard/monitor. Needless to say, we hear every little noise in this build and the 550 GM has been absolutely silent. EVGA brags about their “whisper silent” performance of these units, and it’s true. The fan rarely, if ever, turns on; and this isn’t a bug or bad power supply either, we tested the 650 GM in the same build and experienced the same silent results.

evga 650 gm review

The fan curve is set to be silent until you pass the upper 80% threshold and it will most likely be gaming on overclocked hardware that will push it past that point; what little noise the power supply makes will likely be drowned out by speakers or headphones anyway. It’s most important that a computer be silent when you’re working and focusing on important tasks, silence is truly golden in these scenarios and EVGA’s GM series works very well in such scenarios.

evga gm sfx

All the important protections are present in these units such as over and under voltage protection, over current, power and temperature protection as well as short circuit protection. These units are of course 80 Plus Gold rated which is more than enough efficiency wise. The GM series also operate on a single +12V rail, ensuring clean, consistent power delivery to whichever component needs it.

evga 550 gm review


The pros are numerous for the EVGA SuperNOVA GM series and the cons are non-existent. Our only suggestion for a refreshed or successor unit would be the inclusion of custom, individually sleeved, short length black cables. This would increase the price slightly, however, ITX builders are already accustomed to paying a premium for many of their components and would gladly pay more for custom length sleeved cables.

performance computer editors choice award

We absolutely love SFX power supplies and the EVGA SuperNOVA GM series is the perfect embodiment of what an ideal SFX unit should be: impeccably well-made, fully modular and silent. Buying a quality power supply is extremely important when building any type of computer and EVGA has consistently proved themselves a manufacturer of stout, reliable PSUs. As with all EVGA products, you’ll have access to their top-notch customer service, should you need assistance setting up your unit. The 7-year warranty is a generous one, though we doubt you’ll ever need it.

We highly recommend the EVGA SuperNOVA 650/550 GM SFX power supply units!

Purchase on Amazon

buy on amazon