SilverStone SST-ST45SF Power Supply
Our modification of the SilverStone Sugo SG05 case comes with a bundled SilverStone SST-ST45SF PSU. It is easy to identify the actual maker as the UL code of E190414 on the PSU label refers to FSP.
A power supply from FSP was also used in the earlier versions of the Sugo SG05, but its wattage was 300 watts and it only complied with the basic 80 PLUS efficiency standard.
The exterior of this PSU is hardly remarkable. Its panels are thinner than those of most ATX power supplies and its design is not modular.
The PSU is cooled by a slim 80mm fan which is covered by a vent grid punched out in the case. You can see an “80 PLUS Bronze” sticker nearby. There’s an On/Off switch on the PSU’s back panel.
This PSU is far from advanced in its circuit design if compared to modern ATX products. It lacks dedicated voltage regulation while its Bronze efficiency and active PFC can hardly impress anyone today. We are still impressed, however, that FSP engineers manage to squeeze almost half a kilowatt of power from such a compact PSU.
The PCB is small, so some of the components have to be placed on its reverse side.
A popular PS229 supervisor chip is used for monitoring and protection.
We can also identify a BH0270A chip which is responsible for standby power.
CapXon and Teapo capacitors are installed at the PSU’s output. They are ranked average in terms of quality.
Cables and Connectors
The PSU offers the following cables and connectors:
- One mainboard power cable with a 20+4-pin connector (31 cm long)
- One CPU power cable with a 4+4-pin connector (42 cm)
- One cable with 6+2-pin and 6-pin connectors for graphics cards (42+15 cm)
- One cable with three SATA power connectors (32+21+10 cm)
- One cable with two PATA power connectors and one floppy-drive plug (32+20+20 cm)
The selection of connectors covers any component configurations possible in this computer case but the cables are rather too long as we already said above.
The only thing we can complain about is that the specs are not represented in the traditional easy-to-read table format on the PSU label.
The numbers themselves are good enough. The PSU can deliver most of its power (432 out of 450 watts, to be exact) via the most demanded +12V rail. The load capacity of the +3.3V and +5V rails combined is up to 130 watts. The standby source is rated for up to 2.5 amperes.
The PSU is 80 PLUS Bronze certified and has a 1-year warranty when comes bundled with the computer case. When purchased separately, it has a 3-year warranty (at least on the American, European and Australian markets).
Working together with our APC SmartUPS SC 620, this PSU was stable at loads up to 365 watts when powered by the mains. It couldn’t switch to the UPS’s batteries even at 280 watts, though.
Cross-Load Voltage Stability
The +12V voltage is the most important one for modern computers. It is quite stable with this PSU, staying within 3% of the required level in the typical load range. It is even mostly within 2% except at highest loads.
The +5V voltage is even better. It is almost perfect at typical loads, only differing by more than 2% from the required level at unrealistic loads.
The +3.3V voltage may be more than 3% off the required level at low loads, but is overall stable enough.
Summing it up, this PSU delivers very stable voltages for a product without dedicated voltage regulation.
Output Voltage Ripple
There’s high-frequency ripple on every power rail, especially on the +12V and +3.3V rails, but it is always within the permissible range.
The same goes for the low-frequency ripple.
Temperature and Noise
The PSU is cooled by an MGA8012ZR-O15 fan from Protechnic Electric. It is an 80x80x15mm fan with a rated speed of 4000 RPM.
The fan starts out at 1500 RPM, being virtually silent at such speed. It doesn’t accelerate until a load of 270 watts. After that, it speeds up, reaching 2500 RPM at full load. That’s noisy but not very uncomfortable.
Overall, this PSU is going to be suitable for most users in terms of acoustic comfort. But people who want total silence might be somewhat disappointed.
Efficiency and Power Factor
At the reference loads of 20%, 50% and 100% this PSU was 84.6%, 87.7% and 84.1% efficient. It had its peak efficiency of 88.3% at a load of 246 watts.
These numbers comply by a good margin with the 80 PLUS Bronze standard the PSU is certified for.
The power factor is above 98% at high loads, which is typical of PSUs with active power factor correction.
The standby voltage complies with the industry standard requirements.
The PSU bundled with the SilverStone Sugo SG05-450 computer case features a good combination of wattage, efficiency and noisiness. It does not come cheap, however. The SG05-LITE model, which lacks a PSU and is available in white, costs substantially less.
Most PSUs of the SFX form-factor are inferior in wattage and efficiency to this model, so you can only save money on your PSU by losing the ability to assemble a top-performance configuration.