Legit Power Supply Reviews
Rosewill Capstone 750W Power Supply Review
|Date:||Wed, Oct 10, 2012 - 12:00 AM|
|Written By:||Emmanouil Filladitakis -|
A look inside the Rosewill Capstone 750W
The 140mm fan inside the Capstone 750W unit has been rebranded by Rosewill but from the part number we could instantly identify it as the RL4ZB1402512M fan by Globe, a product commonly found cooling middle-range power supply units. It is a slow 1200RPM model with a long life ball bearing engine.
Even though the Capstone 750W looks almost like a simple generic power supply, cranking it open revealed that the OEM behind this product is Super Flower Computer Inc, one of the most reputable Taiwanese designers of power supplies. The internal quality and craftsmanship is well above average, exactly what an enthusiast would expect from such a manufacturer. It is also interesting to note that this design was clearly meant for modular units, as the excessive clearance towards the back of the unit is obviously meant for a vertical PCB holding the modular connectors.
The filtering stage of this power supply starts directly on the PCB, without any parts at the back of the A/C cable receptacle. On the PCB however there were four Y capacitors, three X capacitors and two filtering chokes. Although these are more parts than required for a standard transient filter, we were unable to locate a MOV. Metal Oxide Varistors (MOVs) are being used for surge suppression, the functions of which have been largely replaced by the active PFC circuits; however, this could still indicate that this unit's tolerance against lighting and or switching surges is limited.
A large Nippon Chemi-Con 560um/400V 105°C capacitor is present at the primary side of the unit, next to a massive PFC choke. The two transistors and the diode forming the APFC circuit as well as the primary side pair of power transistors forming the LC resonant converter have all been placed on a single long heatsink.
The transistors of the synchronous rectifier can be found on the smaller black heatsink and the DC to DC conversion circuits are present on the large vertical board on the secondary side of the unit. All of the secondary side capacitors, electrolytic and polymer alike, are made by Nippon Chemi-Con as well.
Next Page - Test Setup
Page 1 - Rosewill Capstone 750W Power Supply Review Introduction
Page 2 - Unboxing the Rosewill Capstone 750W
Page 3 - External Design
Page 4 - A look inside the Rosewill Capstone 750W
Page 5 - Test Setup
Page 6 - Testing results (Regulation & Ripple)
Page 7 - Testing results (Efficiency, Noise & Thermal)
Page 8 - Rosewill Capston PSU Review Conclusion