SilverStone FX350 is gold rated Flex ATX PSU, good for low to mid range SFF PC’s. If your looking for Flex ATX PSU for mid to high end PC’s, we recommend the FX500, which brings some improvements over the FX350-G.
|FORM FACTOR||Flex ATX (Standard)|
|CERTIFICATION||80 Plus Gold|
|DIMENSIONS||81.5 x 40.5 x 150mm (W x D x L)|
|RATING||Rated for 350W continues power output at 40°C|
|OPERATING TEMPERATURE||0°C ~ 40°C|
Short Circuit Protection
|FAN SPECIFICATIONS||Jamicon KF0415B1HR-R|
40x15mm, 12V, 8.84 CFM, 7300 RPM, 32.9dB(A)
|CONNECTORS||1x 20+4 PIN (350mm)|
1x 2 PIN (300mm)
1x 4+4 PIN EPS / ATX 12V (450mm)
1x 6 PIN PCIe (350mm)
3x SATA (350mm / 150mm / 150mm)
2x 4 PIN Molex (350mm / 150mm)
1x 4 PIN Floppy Adapter (350mm)
|MOTHERBOARD||GIGABYTE B550I AORUS PRO AX (Amazon Link)|
|CPU||Ryzen 5 5600X (Amazon Link)|
|CPU COOLER||Noctua NH-L12S (Amazon Link)|
|GPU||GIGABYTE RTX 3060 Ti Gaming OC (Amazon Link)|
|PSU||SilverStone FX350-G (Amazon Link)|
|RAM||Corsair VENGEANCE LPX 16GB (2x8GB) 3600MHz C18 (Amazon Link)|
|STORAGE||Bootdrive: 256GB M.2 NVME (Amazon Link)|
Gamedrive: 1TB M.2 NVME (Amazon Link)
PRICE & AVAILABILITY
Flex ATX PSUs can be costly in most global regions and not the easiest to obtain, thankfully the SilverStone’s FX350 is reasonably priced at £59.99 and easily obtainable within the UK, Europe and US, most of the time. In comparison to other Flex ATX power supplies.
DESIGN / FEATURES
The FX350 has an almost all black design which fits discreetly into most PC builds. The included cables are mustard in colour, thankfully SilverStone have included some black braided sleeving, so the mustard cables won’t be as noticeable.
The PSU has an included power switch, which is handy and not present on any other Flex ATX power supplies available on the market, other than their own FX500.
Flex ATX PSUs are mostly intended for use in smaller enclosures and the FX350 includes several SATA / Peripheral connectors which can make cable management difficult, and serve to further restrict airflow in already restrictive cases. In our experience, only 1x of each connection type is typically required (if at all).
|FAN MODEL||Jamicon KF0415B1HR-R|
|IDLE / BROWSING||42dB(A) @60CM|
|4K VIDEO EXPORTING||47dB(A) @60CM|
|TIMESPY STRESS TEST||52bB(A) @60CM|
|CPU-Z + MSI KOMBUSTOR STRESS TEST||53dB(A) @60CM|
WATTAGE / POWER DRAW
SilverStone FX350 is gold rated unit, allowing it can operate at its max rating of 350 watts for longer due to its higher efficiency than an equivalent bronze rated unit. The FX350-G peak wattage is estimated 400W.
Total system powerdraw during stress testing reached 340W with all our hardware using stock or out of the box settings. We were able to reduce the system powerdraw by undervolting the RTX 3060 Ti using MSI Afterburner which reduced power draw by roughly 10W (without losing performance).
We changed the GPU voltage curve at 900mV to stable GPU frequency of 1925MHz and overclocked the GPU memory to 600MHz. Your undervolting specifications may vary, depending on the GPU. This improved GPU performance vs stock settings in TimeSpy Benchmark.
NOCTUA FAN SWAP
If your considering swapping out SilverStone’s included fan for something quieter like Noctua, there are some things you need to know.
SilverStone’s included fan is non-standard at 15mm thickness. Noctua’s fans are either 10 / 20mm thickness. This rules out using Noctua’s quiet 40x20mm fan with the FX350-G unit. Noctua’s 40x20mm is also not rated to move enough air at just 5.5 CFM.
If your considering using 10mm thick fan, you’ll be at high risk of the PSU overheating under heavier loads as Noctua’s 40x10mm fan is only rated at 4.8 CFM. The Noctua fan cables would also need reversed for some of the connectors as SilverStone FX350 uses a different polarity on their included fan than Noctua’s, so the Noctua fans won’t spin without it being rewired. This configuration may be suitable for low wattage / power draw builds / setups. The fan noise from the Noctua 40x10mm FLX is so quiet, it’s almost non-distinguishable from rest of the system noise.
You will be safer using the 40x15mm Delta AFB0412LB-R00, which is rated for 6.5 CFM airflow with max fan speed of 5000 RPM and 18.5dB(A) rating. Although this still does not meet the stock fans airflow rating of 8.4 CFM, its a better choice than Noctua’s 40x10mm fan at just 4.8 CFM.
DELTA FAN SWAP
There’s one compatible fan which is 40x15mm thick, which exceeds airflow specifications of the stock fan while also being bit quieter. The Delta AFB0412HB is rated at 9.6 CFM and spins upto 7000 RPM with noise rating of 28.5dB(A).
The Delta fans positive and negative cables at the PIN connector will require being swapped around as shown in the 3rd image below for the fan to spin.
We set the fan as intake for best results as in most cases, you will want to be pulling cold air into the FX350-G from outside the case vs pulling hot air from inside the case.
DELTA AFB0412HB – NOISE TEST
|FAN MODEL||DELTA AFB0412HB|
|IDLE / BROWSING||38dB(A) @60CM|
|4K VIDEO EXPORTING||42dB(A) @60CM|
|GAMING||43 ~ 47dB(A) @60CM|
|TIMESPY STRESS TEST||50bB(A) @60CM|
|CPU-Z + MSI KOMBUSTOR STRESS TEST||51dB(A) @60CM|
Any modifications to the SilverStone FX350-G PSU will void the warranty and may produce suboptimal performance.
FULL REVIEW / OVERVIEW
The FX350-G power supply is best suited for low & mid tier ITX PC builds. If you planning on running 65W+ TDP CPU and RTX 3060 Ti or higher, our recommend PSU would be 400 ~ 450W Gold Rated unit.
If you don’t mind doing a little system tweaking, you can run the Ryzen 5 5600X and an RTX 3060 Ti on 350W Gold Rated power supply without instability as demonstrated in this review. However we still recommend using the SilverStone FX500 instead.
In cases as small as what’s intended for Flex ATX, it’s always a good idea to tweak your system to improve system thermals as components can get hotter than they otherwise would in larger cases.
We absolutely recommend the SilverStone FX350, as it ticks alot of the right boxes. The downside for us was the extra cables which made it more difficult to get everything to fit in 4L enclosure, of course this is personal circumstances / use case experience. We’re putting this down to having and not needing, then needing and not having which isn’t a bad thing either. Plus the FX350-G has been available for a while at this point so the Floppy, Molex and Sata connectors were more standard and in some cases still are today.