By: Alford Xue (Guest Editor)
January 30, 2026
I have recently just returned to university classes with the start of the winter semester, and just looking at my schedule is enough to make me feel a bit tired. Four of my classes include labs and group projects, so this is shaping up to be a very busy term. Balancing all of that alongside an ongoing internship search means priorities naturally shift toward making practical decisions within clear constraints. Time, energy, and flexibility are limited, and chasing an idealized “perfect” outcome is often less useful than identifying solutions that fit the situation at hand. Often, it is less about maximizing every opportunity and more about making the best choices given what is feasible in the moment, or going with the flow while still doing the best you can. The same mindset applies to small form factor PC builds, where physical space, thermal limits, and platform requirements place hard boundaries on what makes sense. In these constrained environments, power supply selection is not just about picking the highest wattage you can find. Rather, it is about choosing a unit that aligns with the realistic demands of the system it will support. A 650W rating might look restrictive when viewed in isolation, but its suitability depends heavily on the design goals and limitations of compact builds. So, can a 650W SFX power supply still deliver the balance, stability, and modern features needed for today’s small form factor systems? Read on to find out.
Today’s review unit of the Extreme 650Rz Gold 650W came from SilverStone’s offices in Chino, California. The cardboard shipping box arrived in good condition, despite having minor dents along the edges. One aspect I was not a huge fan of was the inclusion of Styrofoam packing peanuts inside the box. While they protect the contents during transit, they are inconvenient to clean up. This power supply was the only product inside the shipping box.
The retail container of the SilverStone Extreme 650Rz Gold 650W features the company’s classic navy blue and gold color scheme. The box has a SilverStone logo in the top left corner, the product name printed underneath. Additionally, a scaled image of the power supply unit appears on the right side of the box. A tagline reading “80 PLUS Gold 650W SFX12V 4.1 PCIe 5 Fully Modular SFX Power Supply” is printed below the product name. At the bottom, it is clearly indicated that this is a 650W power supply. Several notable features are highlighted, including compliance with SFX12V V4.1 and PCIe Gen 5 standards, as well as an 80 PLUS Gold efficiency rating.
Here are the specifications from the manufacturer’s website:
Product Number: SST-EX650R-GM
Model (Safety Certification): SST-SX0650MCGD-A
Color: Black (lead-free paint)
Max. DC Output: 650W
Power Density: 818.9 W/L
Combined +3.3V and +5V: 100W
Combined +12V: 650W
Input Voltage: 90 ~ 264 Vrms
Input Frequency Range: 47Hz ~ 63Hz
PFC: Active PFC（PF>0.9 at full load)
Efficiency: 87% ~ 90%
MTBF: 100,000 hours
Operating temperature: 0°C ~ 40°C
Protection:
- Over Current Protection
- Over Power Protection
- Over Voltage Protection
- Short Circuit Protection
- Over Temperature Protection
- Under Voltage Protection
Connectors:
- 1x 24 / 20-pin motherboard connector
- 2x 8 / 4-pin EPS / ATX 12V connectors
- 4x 8 / 6-pin PCIe connectors
- 6x SATA connectors
- 3x 4-pin peripheral connectors
Cooling System: Single 92mm fluid dynamic bearing silent fan
Noise Level: 0 dBA minimum
Certification: 80 PLUS Gold
Form Factor: SFX
Dimensions:
125mm (W) × 63.5mm (H) × 100mm (D), 4.92" (W) × 2.5" (H) × 5.12" (D)
Weight: 1.36 kg
Warranty: Three years
Load Range:
Output: +3.3V, +5V, +12V, +5VSB, -12V
Max. (Amps): 20A, 20A, 54.1A, 3.0A, 0.3A
Min. (Amps): 0A, 0A, 0A, 0A, 0A
Range (%): ±3%, ±3%, ±3%, ±3%, ±10%
Line Regulation (%): ±1%, ±1%, ±1%, ±1%, ±1%
Ripple (mVp-p): 40mV, 40mV, 80mV, 40mV, 80mV
Inside the box, the SilverStone Extreme 650Rz Gold 650W is split into two primary sections. On the left side, the power supply is in a transparent plastic bag and cushioned between two large black polyethylene foam inserts. On the right side, separated by a SilverStone cardboard divider, are the modular power supply cables, an SFX-to-ATX mounting bracket, and mounting screws. Each connector is packaged in their own respective bags or bundles. The box also includes a printed specification sheet and a multilingual user’s manual.
The SilverStone Extreme 650Rz Gold 650W comes with a three-year warranty, which is consistent across SilverStone’s recent Gold-rated power supplies. Only the company’s Platinum and Titanium SFX models receive five years of coverage. Considering many competing power supply manufacturers offer warranties lasting up to ten years, the coverage provided here is comparatively short.
Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion
