Seasonic FOCUS Plus 850 Gold 850W (Page 2 of 4) | Reports

Page 2 - Physical Look - Outside

The Seasonic FOCUS Plus 850 Gold 850W has a relatively compact size for an ATX power supply. In terms of dimensions, this power supply stretches out 14.0cm, which is pretty good. It should be noted fully modular power supplies generally take up more room compared to their semi-modular or non-modular counterparts by a centimeter or two, as this extra real estate is used for the connector board at the back. We will explore what this looks like later when we delve into the Seasonic FOCUS Plus 850 Gold 850W. For most ATX or eATX chassis, this sort of length will be almost a non-issue. However, for smaller mATX or mITX cases, the extra length may be more difficult to deal with, even if it is only a few centimeters. In the end, your mileage will vary based on your build.

From the top of the photo here, you can see the Seasonic logo smacked in the middle with horizontal bars to allow air to the fan. These metal bars running across the 120mm internal fan act as a grille to stop larger debris and objects from entering, all while not impeding airflow significantly. Otherwise, the sides of the power supply are finished in a smooth black look, with some small but noticeable engraved accents around the box. The sides show off the FOCUS Plus Gold branding. At the back, we have exhaust vents in a standard honeycomb pattern. This allows excess heat to leave out the back of the power supply. The external casing of the power supply is held together with four screws at the top near the fan, with one screw having a warranty seal over it. The only way to get inside this unit is to void the ten year warranty, which is not advisable to do.

Starting from the back, we once again have the honeycomb pattern. This uniform design is generally favored not for its aesthetics, but rather for maximizing airflow while minimizing air resistance. The back vents play an essential role in allowing heat to flow out the back, and having better airflow means it will get out as efficiently as it can. Most modern power supplies have an automatic full range (100V-240V) AC line voltage selection, so you will not need to manually flip an additional switch, and this product is no exception. Therefore, the back has a single power switch and a standard power input. Thankfully, this is not a C20 receptacle, like the ones we have seen on some power supply units. We also have a push button switch with a label of "Hybrid Mode". As the name implies, this switch enables the hybrid silent mode for the fan. According to Seasonic, when this switch is not pressed, the fan will remain off at loads less than 30% of the maximum 850W.

Like most of the recent power supplies we have covered here at APH Networks, the Seasonic FOCUS Plus 850 Gold 850W is a fully modular power supply. This means all cables are completely detachable from the main unit. While some users may question the necessity of this for essential cables like the ATX 24-pin and the ATX 4-pin/EPS 8-pin, there still are benefits to having this. For example, I would argue this makes cabling easier, since users can pre-route the cables without needing the power supply installed right away. Secondly, there are a few third party manufacturers who provide sleeved cables for power supplies, and this is only made possible by fully modular units. On the other hand, there is a higher, but very negligible, electrical contact loss at the connectors compared to permanently fixed cables. At the end of the day, your preference will make the final call, but I would stick to fully modular units.

The rear cable connection panel is clean, with similar connectors grouped together and laid out logically. They are clearly labeled, so you know which plug is for what. On the top row, we have the motherboard pins. Next to these are two sets of eight pin connections, used for either the CPU output, or the PCI Express connectors. On the bottom row, we have four sets of six pin connections. These are used for the peripheral outputs for IDE, SATA, or Molex connections. Finally, we have three more PCI Express connectors, though this area can also be used to power the CPU. It is great to see Seasonic provide this many connectors, which should be sufficient for most users and even power enthusiasts too.

The external build quality of the Seasonic FOCUS Plus 850 Gold 850W is excellent, but this is no surprise for Seasonic and their units. We will take apart the FOCUS Plus 850 Gold unit in a moment. Otherwise, the fit between the panels is quite good with very little gaps in between. The edges are finished off nicely, and is comparable to other units we have seen in the past. Of course, what matters is the inside, and we will see what they are like soon enough.

The voltage specification label for the Seasonic FOCUS Plus 850 Gold 850W is on the opposite side of the fan. There are two main virtual rails. Up to 20A can be delivered via the +3.3V rail for a total of 66W. The +5V rail can deliver 20A too, bringing the output to 100W in this area. The total combined output for the +3.3V and +5V rail is 100W. In other words, your power allocation combination must fall within the limits of the listed specifications. Meanwhile, a single powerful +12V rail delivers up to 70A (840W) to reduce operating overhead compared to multiple +12V rails. Overall, the combined power output for the whole FOCUS Plus 850 Gold 850W is an unsurprising 850W. There is a 10W difference between the +12V line and the total output. Again, your power distribution in your system must fall within the limits provided -- it must not exceed 66W on the +3.3V rail, 100W on the +5V rail and 100W combined for both, 840W on the +12V rail, and 850W combined between the positive rails. All these confusing numbers aside, this configuration allows for flexible power demands. It should be sufficient to accommodate most users, but it is interesting to see the lower power output on both the +3.3V and +5V lines. Even so, the overall distribution is pretty reasonable for an 850W power supply.

The Seasonic FOCUS Plus 850 Gold 850W is 80 Plus Gold certified, which means it is certified to be at least 87%, 90%, 87% efficient at 20%, 50%, and 100% load, respectively. Seasonic also has the FOCUS Plus lineup with an 80 Plus Platinum specification for even better efficiency. While the Gold rating may seem a bit pedestrian for a power supply in 2017, I think this is completely fine, considering the target audience for this unit and lineup.

A total of eleven modular cables are included out of the box, plus one small adapter. All of the peripheral cables, including the SATA, Molex, and Floppy adapter are flat ribbon cables, while the motherboard, CPU, and PCI-E cables are sleeved with black webbing. The flat-ribbon cables are generally quite easy to bend, but the braided cables are a bit stiffer. It should be noted some the braided cables have in-cable capacitors, which make them a bit less flexible. These wires are 18AWG, which should be able to handle most high currents found through PCI Express and ATX/EPS connections.

The following modular cables are included out of the box:

- 1x ATX 20+4 pin, 61.0cm
- 2x ATX/EPS 4+4 pin, 65.0cm
- 3x PCIe 6+2 pin, 2 connectors each, 67.5cm to first connector, 7.5cm spacing thereafter
- 2x SATA, 4 connectors, 45.0cm to first connector, 12.0cm spacing thereafter
- 1x SATA, 2 connectors, 35.0cm to first connector, 12.0cm spacing thereafter
- 1x Molex, 3 connectors, 45.0cm to first connector, 12.0cm spacing thereafter
- 1x Molex, 2 connectors, 35.0cm to first connector, 12.0cm spacing thereafter

These measurements are specified from the manufacturer. Most users should have no problems using these cables with the FOCUS Plus 850 Gold, even if the power supply is in the basement of the case. Fifty centimeters is the general standard between the power supply connection and the first connector, but the shorter peripheral cables may be advantageous in routing management with modern cases. The 12cm spacing between connectors is also adequate between multiple drives. I still question why power supply manufacturers even include floppy connectors nowadays, as floppy drives are practically relics now. Thankfully, this is just a Molex to Floppy adapter, so you can ignore it altogether.

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