The SilverStone Extreme 850R Platinum is an 850W, SFX form factor, fully modular ATX 3.0 power supply with a hybrid fan mode, priced at $269.99 USD MSRP.
Labs conducted tests on two samples of this power supply. The first sample failed during dynamic load testing, with the cause of the failure unknown. The second sample completed all tests successfully. The failed sample has been returned to SilverStone, and they are investigating the cause. Updates will be provided as more information is available.
Update as of 15-Aug-2024: We have received a full incident report from SilverStone on the first failed sample. Upon their investigation, they found a dead component related to the control of the -12V rail. They replaced this component and the PSU resumed regular function. They have not had any other reports of failures of this sort, but will monitor for similar cases going forward.
WHAT YOU NEED TO KNOW
THE GOOD
- Efficiency
While it does not carry any 80PLUS ratings, the power supply boasts good efficiency, achieving a Cybenetics Platinum rating.
- Form Factor
As an SFX form factor power supply, it's ideal for small form factor cases and compatible with all ATX-supported cases when using the included adapter bracket.
THE BAD
- Cables
The included webbed cables are quite stiff, making it difficult to handle when cable managing.
- Warranty
The 5-year warranty is shorter than average for similarly priced and rated power supplies.
THE REST
- Overall
We recommend the Extreme 850R Platinum for its good efficiency and small form factor.
- Performance
While the general performance is good throughout the whole test suite, it has a few caveats in each section. These all comply with specifications and are unlikely to cause significant problems.
*This website uses affiliate links. Purchases made through these links may provide compensation to Linus Media Group.
The Extreme 850R Platinum is a compact SFX form factor power supply, smaller in all dimensions compared to an ATX form factor. It can be used in ATX-supported cases with the provided adapter bracket.
Along with the standard accessories, the webbed construction cables are well-insulated but stiff, posing challenges for cable management. The included 12VHPWR cable is rated for 450W.
The power supply features a Regular Fan mode and an Intelligent Fan Stop mode, controlled by a physical on/off button. The fan measures 92mm. On the SilverStone specifications webpage it specifies that the Operating Temperature is 0°C to 50°C, though we cannot verify this through testing.
1 of 4
Front of the box.
1 of 2
Power input side of the PSU.
Top of the PSU displaying the fan.
Bottom of the PSU displaying the specifications.
| +12 V | +5 V | +3.3 V | +5 Vsb | -12 V | |
|---|---|---|---|---|---|
| CURRENT | 70.8 A | 20 A | 20 A | 3 A | 0.3 A |
| WATTAGE | 850 W | 100 W | 15 W | 3.6 W | |
| 850 W | |||||
Please note that the above ratings are manufacturer advertised specifications.
The Extreme 850R Platinum has two fan modes, Regular mode and Intelligent Fan Stop mode. The user manual specifies that the fan will remain off for loads less than 110W, activating when the internal temperature exceeds the safe range or when the load surpasses 200W.
The power supply is equipped with standard protections, but is supported by a 5-year warranty, which is shorter than average for its class.
The Extreme 850R Platinum displayed good performance in testing, with relatively good voltage ripple on the 5V and 3.3V rails, though the 12V rail was a bit noisy, which is unexpected for this price and efficiency rating.
It showed good load regulation, with some drop on the 12V rail compared to other premium power supplies. It generally maintained above 12V at low wattages.
The power supply sustained all power excursion tests, though the 12V rail dipped below specifications during the 0.1 ms excursion, which is unlikely to affect reliability for most workloads.
1 of 6
The Extreme 850R Platinum does not have an 80PLUS rating but is rated at Cybenetics Platinum, offering good efficiency comparable to 80PLUS Platinum power supplies, with 92% efficiency at 50% of its maximum load.
It handles brownouts reasonable well, with output voltages remaining stable. The power supply’s ‘Power Good’ signal will shut it off after a 14 ms brownout at full load.
The Over Power Protection engaged at a maximum of 149% of the rated load, while the 12V rail is capable of 97A, or 137% of its rating. The Over Current Protection for the 5V and 3.3V rails is slightly low, engaging at 23A above their rated 20A. The 12V rail has a solid 137% OCP, where most power draw occurs.
