Enermax PlatiGemini 1200W ATX v3.1 & ATX12VO PSU Review: The first of its kind!

Part Analysis

top1

top2

top3

top4

transienta1

transienta2

MOV

NTC_&_relay

bridge_rectifiers

APFC_FETs1

APFC_FETs2

boost_diode

bulk_caps

APFC_controller

main_FETs

main_transformer

12V_FETs

minor_rail_Controller_FETs

cap1

cap2

cap3

cap4

5VSB_rectifier

5VSB_transformer

modular_board1

modular_board2

modular_board3

SPN5003

standby_PWM_controller

supervisor_IC

main_PCB1

main_PCB2

main_PCB3

fan

fan_close

I am always excited to see a new platform! This is by RSY, an OEM that used to work closely with Super Flower and later handled some of Seasonic’s PSU production. This platform is unique since it delivers two standby rails simultaneously, although not in the most efficient way. I will explain what I mean. To offer ATX12V and ATX12VO compatibility, the platform has two different configurations, one with the typical rails and 5VSB and one with only 12V and 12VSB. Eliminating the minor rails and 5VSB is easy since the only thing you have to do is use a cable that won’t use the corresponding pins, but having 12VSB is a pain since you have to implement a second rail in the PSU’s standby circuit. In this PSU, this is precisely the case; while on standby, if you get a multimeter and probe the sockets that power the ATX cables, you will find both 5VSB and 12VSB. Ideally, these rails should be generated only when needed (when the corresponding pins are used) and not continuously since this can affect standby (or Vampire) power. Of course, the easiest and trouble-free way is to have them operate in parallel continuously, but this way, a small amount of energy goes wasted. The same goes for the DC-DC converters of the minor rails, which ideally should be completely switched off once the 12VO cable is connected to the PSU.

The platform’s modern and clean design has enough space between parts for decent airflow. I also like that the AC socket is attached permanently to the PCB, so you don’t have to desolder any cables to get the PCB out of the casing. To minimize energy losses, the 12V FETs are installed on a vertical PCB, which is right beside the main transformer, while the DC-DC converters generating the minor rails are close by. Because of the small PCB size, several daughter boards are used to save space and optimize the design.

We find a full-bridge topology and an LLC resonant converter for lower energy losses on the primary side. All parts are of high quality, including caps by Chemi-Con and Rubycon. In addition to electrolytic caps, many polymer caps handle ripple filtering on the PSU’s secondary side.

The standby circuit generates the 5VSB and 12VSB rails by utilizing a single rectifier on its high side and two Schottky barrier diodes (SBRs) on its secondary side. I followed the PCB traces to identify these SBRs and the respective rectifying circuits.

The cooling fan is by Zeta Group, a brand I first noticed in Super Flower’s new PSUs. This doesn’t sound strange, given RSY’s close ties with Super Flower. According to SF, this new fan brand is pretty good, which could end Hong Hua’s dominance in the field. Well, we will see that in the future.