Efficiency, Differential Temperature and Noise
Efficiency
Efficiency is defined by the power output divided by the power input and is usually expressed as a percentage. If a PSU were a 100% efficient (which none are) 650 watts of AC power going in would result in 650 watts of DC power coming out (with no waste heat to dissipate). In the real world there are always inefficiencies and power is lost in the form of heat during the conversion process. Newer revisions to the ATX12V Power Supply Design Guide V 2.2 have continued to increase the efficiency recommendations for PC switching mode power supplies and now lists both required and recommended minimum efficiencies.
We measured the AC power input to the Seasonic FOCUS PLUS 650W Gold PSU with an Extech power analyzer while the total DC load was found by adding all the individual +3.3V, +5V, +12V, -12V and +5VSB loads together.
The overall efficiency of the FOCUS PLUS 650W Gold power supply is very good and easily meets the criteria for 80 Plus Gold certification, even while operating on 120VAC and at elevated temperatures.
80 Plus Program
Note: Tests conducted at room temperature (25°C)
Differential Temperature and Noise Levels
To simulate a demanding environment, some of the warm exhaust air from the PSU under test is recirculated back to the intake through a passive air duct, which allows the PSU air inlet temperature to increase with load, up to 40°C.
The differential temperature across the power supply was calculated by subtracting the internal case air temperature (T in) from the temperature of the warm exhaust air flowing out the back of the power supply (T out).
Thermocouples were placed at the air inlet and exhaust outlet. The ambient room air temperature was 23ºC (74ºF) +/- 0.5ºC during testing.
T out = temperature of air exhausting from power supply
T in = temperature of air entering power supply
Delta T = T out – T in
Sound pressure level readings were taken 3’ away from the rear of the case in an otherwise quiet room. The ambient noise level was ~27 dBA. The Hybrid Mode was engaged to enable fanless operation at the lower power levels.
*Fan not spinning
The FOCUS PLUS 650W Gold PSU started out dead-quiet and stayed that way up through the 50% load mark. Above 50% load the cooling fan gradually increased in speed and the noise eventually became very noticeable at full load as the fan did its job but never did become subjectively loud.
(Courtesy of Seasonic)
Good read – and good to see
Good read – and good to see Seasonic on top of their game yet. I’m due for a new build soon and this looks like a really good option.
My main gaming PC is running a 10 year old Seasonic M12 SS-600HM and it’s still going strong through a couple board/CPU upgrades and multiple graphics card upgrades.
It is good that PSU
It is good that PSU manufacturers understand that the 230 mm power supplies of half a decade ago are not really needed anymore. Sure, it may look cool to some because they believe bigger to be better, but a short power supply for anything under a kilowatt is just fine given proper design.
I just need a reason to
I just need a reason to change my 7 year old seasonic that is serving its 3rd build.. But am feeling guilty of replacing a perfectly good, reliable and working PSU that has no problems.. Damn you Seasonic.
Well done Seasonic-you set
Well done Seasonic-you set the standards by which
others are measured…………
The box art is making me
The box art is making me hungry for chips.
This PSU seems to be of
This PSU seems to be of insane value as it is smaller, better AND cheaper then the Corsiar RM650x!
“our PSU was delivered
“our PSU was delivered straight from Newegg.com inventory.” On front page yet last page says “Our thanks to Seasonic for sending us the FOCUS PLUS 650W Gold PSU to review!” Guess they are getting the cherry picked samples.
It ordered by Seasonic from
It ordered by Seasonic from reseller’s stock… Good job Sherlock to find out nothing… 😉
650RM vs 650FX, 650RM “old
650RM vs 650FX, 650RM “old model” is better than the “new” 650FX
why?
the old had more available cables such as 4+4 attached for cpu power and an extra 1×8 12v for cpu as well, this way here you did not need buy a higher wattage PSU that you will not need for nothing.
some builds that you may have an extra powerful cpu you may not have need of an extra power gpu, but even than, 450w of power is quite a bit of juice for even a very high end core i7 overclocked as well as pretty much any modern AMD or Nvidia graphics card (single one at least) in an overclocked state, so 54a 12v is plenty really, this saves you from having to buy an adapter for the extra cpu power (which quite a few motherboards are now using)
Seasonic is top quality bar none, but, it seems they took a hit on functionality “upgrading” from the semi-modular 650RM to the full modular 650FX, not quite as much in the 3v or 5v rails as well as a few cable change but also costing on average a little bit more $.
glad I bought the 650RM….as well, the cables that are not modular 99% of the time you will be using them anyways ^.^
Hello, do you have maybe
Hello, do you have maybe cab;e pinout for focus plus series?
Hey guys should i put into PSU another 8pin cable for my new 3080 OR it will be enough if I stick with one that’s is connected to my 1060 (it has another 8pin plug)
Technically just one cable is enough to support both 8-pin connectors, but I like to use two separate cables when possible. The 3080 is capable of pulling quite a bit over 320 W in instantaneous bursts.
Thanks fo the reply 🙂 i will pług second cable for platform stability 🙂
And one more quick question in second PC i will probably install 3070 (unit with same seasonic psu) in that rig one cable should be totally ok