In-Win Development Inc. has the reputation of a manufacturer of rather inexpensive (their consumer products range from $50 to $70 in price) yet quality system cases for home and office computers as well as for entry-level servers.
In-Win’s cases had used to be equipped with power supplies from FSP Group (originally marked as “SPI, Sparkle Power Inc.”), but a few years ago In-Win launched its own power supply manufacture. These units are currently installed into In-Win cases and also sell separately. The good reputation of the In-Win brand attracts the users’ attention to their power supplies.
Below follow my tests of five PSU models from In-Win’s three different series. Each series includes two models differing in their lacking or having passive PFC, the rest of the parameters being identical. So I deal with them in twos.
In-Win IW-ISP300A2-0 and IW-ISP300A3-1
The only point of difference between these two models is that the A3-1 has a passive PFC device, so I will describe them together. Moreover, the power factor was actually the only parameter the two models differed much in by the results of my tests.
The regulator of the first unit is based on an IW1688 chip, the regulator of the second on an SG6105D chip, but the identical PCBs and accompanying components make me suspect that the IW1688 is nothing else but a remarked SG6105D.
The heatsinks are only 2 millimeters thick, with some ribbing along the entire height. One corner is cut out of the heatsink with the switching transistors: a passive PFC throttle, fastened to the top panel of the PSU, is situated there in the A3-1 model. A standard two-section line filter is installed on the PSU’s input. The capacitors on the input of the high-voltage rectifier have a 470µF rating each.
There’s a rather confusing situation with the wattage of the unit. On one hand, the In-Win website clearly declares 300 watts for the ISP300A2-0 model, but on the other hand, the PSU’s own label reads “+3.3V & +5V & +12V = 235W (Max)” (see the snapshot above). The remaining voltages (the two negative voltages plus the standby voltage source) may total to 21 watts at best. So, the resulting wattage of this power supply is 250 rather than 300 watts.
The same conclusion comes from the maximum allowable currents: they exactly match the industry standard recommendations for 250W power supplies. So, there can’t be two opinions – this unit is a 250W power supply. The same strange thing about the declared wattage occurs with the ISP300A3-1 model, by the way.