Seasonic M12II 500W (Page 2 of 4) | Reports

Page 2 - Physical Look - Outside

Like the original Seasonic M12, the M12II retains the same subtle design -- no fancy colors, no fancy LEDs. The black matte finish of the power supply evokes a sense of elegance and cleanness on its own. At the back is the same honeycomb mesh design to maximize airflow and minimize air resistance. This is done as heat needs to leave the power supply as easily and efficiently as possible, because the Seasonic M12II incorporates only one 120mm fan at the bottom. Standard power supply on/off switch is located to the right of the male connector for power input. As with most new power supplies, the Seasonic M12II has an automatic full range (100V-240V) AC line voltage selection, so the user does not have to worry about manually selecting input voltage.

Being used to large, high power PSUs, I found the Seasonic M12II 500W to be fairly small -- a quick measurement indicated that the M12II is really 2cm longer than the standard 14cm to allow room for the modular connectors, but really -- it's hard to find a real quality power supply at those dimensions nowadays anyway.

Flipping the power supply around both on the X-axis and Y-axis reveals the bottom mounted 120mm fan and the modular cable connectors at the back. The 120mm fan (Which we'll have a closer look later, when we crack open the Seasonic M12II 500W) resides behind an eight ring fan grille, again well designed to minimize air resistance. Four screws on each side of the M12II secure the power supply case together; where one side has a warranty seal on -- so you can't open the power supply without voiding the warranty.

The only non-modular cables are the ATX 24-pin, ATX 4-pin, and EPS 8-pin connectors. The rest are all removable; there are two PCI Express and six Molex/SATA output connectors at the back of the power supply. The included cables generally provide an excellent amount of connectors -- tons of SATA, tons of Molex, and one of the PCI Express power connectors are the 8-pin ones -- for one 8-pin and one 6-pin PCIe power connector in total.

One of the biggest improvements made to the M12II is the removal of the rear 60mm fan. The original M12's 60mm fan is designed to activate at a higher voltage than the main 120mm fan, as they are connected to the same header internally -- otherwise both will turn on at the same time. This is made possible if the M12II is more efficient and generates more heat, but from what I can see the 120mm fan spins and higher RPMs quicker than the original M12 at the same time. After all, air can only enter from the bottom of the power supply and exit out the honeycomb mesh at the back -- no other vents are implemented.

The voltage specification label on the side of the Seasonic M12II. I found this a bit interesting because it is rated lower than the Seasonic M12 -- the Seasonic M12 500W allows a maximum of 24A on the +3.3V rail, and 30A on the +5V rail for a combined total of 170W maximum output. The Seasonic M12II had the 5V rail reduced to 24A, for a combined output of 130W on the +3.3V and +5V rails. For the 12V rail, the original M12 has four virtual rails for a combined output of up to 38A (456W); however the Seasonic M12II dropped it to two virtual +12V rails that can be fully utilized at 17A+18A for up to 420W output. The combined for all voltage rails are 500W, making the Seasonic M12II 500W a... 500W power supply. Anyways, either way these are decent numbers for a 500W power supply, and from an engineering standpoint this reconfiguration of rails would probably make power delivery a bit more efficient than before. I can't imagine anyone pulling 456W on the +12V rail out of a 500W power supply anyway.

As previously mentioned, the following detachable cables are included:

- 2x SATA power cables, 3 devices each (6 total)
- 3x Molex power cables, variable devices each (8 total)
- Y-adapter for Molex to 4-pin FDD (2 devices total)
- 1x PCIe 8-pin
- 1x PCIe 6-pin

With the ATX 24-pin, ATX 4-pin, and EPS 8-pin connectors non-removable. These cables are all decently long; I've had no problems installing the power supply on a bottom chamber design or a standard top implementation -- the cables have the necessary length to reach where power is needed. All cables are fully sleeved for aesthetics and cabling convenience. The cables are designed so that you cannot plug them in the wrong orientation or direction. To be honest, it's very well executed too with regards to length and power connector placements -- in my setup where I have the M12II installed, I only used one Molex cable to power all my devices (One hard drive, one DVD burner, and a bunch of case lights).

As far as the connectors go, they connect securely and don't feel cheap at all -- but when you need to disconnect them, the clips are easy to unlatch. Notice that the 4 pin ATX12V block and 8 pin EPS12VEP block are separate cables. Last time I checked, it has something to do with a power supply design standard requirement, therefore a single 4+4 pin block is not implemented instead -- although I personally haven't seen many manufacturers follow this design scheme.

Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion