A Look Inside

Before reading this page we strongly suggest to take a look at this article, which will help you understand the internal components of a PSU much better.


The design used for the heatsink(s) is the trademark of Enhance, the OEM who built this unit for Coolermaser. The main PCB is quite long and occupies all the internal space of the roomy case and the heatsinks, especially the primary, are way too big for a Gold PSU which has low energy dissipation, but on the other hand big heatsinks lead to reduced fan speeds thus lower noise output. The PSU does not use an LLC resonant converter or a full bridge topology to achieve Gold efficiency, so we don't expect to see ground breaking efficiency numbers. However the main transformer, thanks to its design, has smaller size and lower operating temperatures so it promises an efficiency boost. In order to give you a better view we fought really hard with the main heatsink and in the end we managed to remove it. However as it proved much later the toughest thing wasn't its removal, but the re-installation process.


As usual we start the internals description from the transient filtering stage. This begins right at the AC receptacle with one X and two Y caps. It continues on the main PCB with two pairs of X and Y caps, two CM chokes, an MOV and a thermistor which is cut off by an electromagnetic relay, once the PSU starts and the APFC caps are charged.


The primary heatsink is a real monster and it holds many parts. For starters two rectifier bridges (GBU15L06) are bolted to it and between the two bridges there is another smaller heatsink. Strangely enough we found no thermal compound between the bridges and the heatsinks, so we applied some. Afterwards we find the APFC mosfets, two IPW50R140CP and the boost diode, an STTH3006DPI. The primary switches, two IPW50R140CP, are also bolted on the primary heatsink and on the opposite side we meet a lonely FQP8N80C. Finally, on the primary heatsink a SEKI ST-22 thermostat (110°C), for overheat protection, is bolted.


The three parallel hold up caps are provided by Nippon Chemi-Con (420V, 330µF, 105°C).


Behind the modular PCB a vertical PCB is hiding. It houses the protections IC, a PS232S, and the combo PFC/PWM controller, a CM6802SBHX.


The standby PWM controller is an A6062H and the SBR that handles the 5VSB rail is an MBR1060.


The main transformer utilizes a hybrid design which combines the heatsink and the transformer into a single unit. This allows for smaller transformer size and reduced operating temperatures which lead to efficiency gains.


In the secondary side synchronous design is used and the +12V rail is handled by four mosfets. The minor rails are generated through +12V with the help of two DC-DC converters. On each VRM an APW7073 PWM controller drives the mosfets. On the VRMs solid state caps are used, while on the rest of the secondary we find only Japan made electrolytic caps (Chemi-Con).


On the front of the modular PCB we find several small electrolytic filtering caps which are provided by Suncon and there are also many SMD caps. On the solder side of the modular PCB there are two large Chemi-Cons which further reduce ripple. As you can see from the photos above the modular PCB is over populated by wires, connectors and caps.


Soldering quality on the main PCB is typical Enhance, not top but definitely well above average. As you can see there are four shunts on the PCB, to provide current sense data to the OCP circuit for four +12V rails, however in this case all are sorted together to form a single rail.


The fan has Cooler Master's logo on it, but it's made by Young Lin Tech and its model number is DFS132512H (12V, 3W, 1700RPM, 36.28dBA, 91.16CFM). At normal RPMs it is quiet but at full speed it's noisy despite the only 36.28 dBA that its characteristics state.