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) 750 watts of AC power going in would result in 750 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 PRIME 750W Titanium 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 PRIME 750W Titanium power supply is excellent and easily meets the criteria for 80 Plus Titanium certification, even while operating on 120 VAC 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, just like it would in a real PC.
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 power supply was tested with Hybrid Fan Control turned On (enabling fanless operation at low to mid power levels).
*Fan not spinning
The PRIME 750W Titanium PSU cooling fan did not start spinning until we were well into the 50% load test. At the 75% load mark the fan noise was still relatively quiet and even at the 100% load mark the fan noise never really became loud. Having great efficiency helps keeps the waste heat and fan noise to a minimum.
(Courtesy of Seasonic)
I’m a little concerned about
I’m a little concerned about the switch from Sanyo Denki fans to Hong Hua, but given that warranty, it seems that Seasonic is confident that the fans will last.
If it’s anyhting like their
If it’s anyhting like their previous PSUs, the fan never spins anyway if you size it slightly bigger than your needs.
Just bought an X850 Gold dirt
Just bought an X850 Gold dirt cheap on Newegg and it has the Sanyo Denki fan.
I’ve been hoping you guys
I’ve been hoping you guys would review this PSU. Good job!
How about coil whine? It will
How about coil whine? It will not show up in normal sound pressure measurements. Did you notice any coil whine?
I had extreme trouble finding a power supply without bad coil whine. I went through several very expensive and recognized brands before settling on the Corsair RM750.
Neither of my Seasonic X
Neither of my Seasonic X Series have coil whine and i am EXTREMELY sensitive to it. My ears fill with fluid sometimes as the result of a back and neck injury, so coil whine(or any high frequency sounds) actually cause me physical pain 🙂
From what i read, this Seasonic will not have coil whine since its coils are encased in something specifically to prevent vibration.
Seasonic or something they
Seasonic or something they have created for OEM is the only power supplies I buy, but usually they have a really understated design, a shame they have gone away from that, this is starting to remind me of something “gaming” branded!
i’m using Seasonic X-750
i’m using Seasonic X-750 (KM3) but frankly speaking, Seasonic had the highest & the worst failure rate ever.
Wheres the data?
Wheres the data?
I had a X-series 750 blow a
I had a X-series 750 blow a cap. but they replaced it really quick. Excellent Customer Service
https://www.techpowerup.com/f
https://www.techpowerup.com/forums/threads/quality-seasonic-psu-kicks-the-bucket-early.213005/
http://www.hardware.fr/articles/947-6/disques-durs.html
dude, google is your friend. please don’t denied that Seasonic higher failure rate.
by the way, i’m Seasonic fan-boy.
650W versions apparently got
650W versions apparently got delayed because the cables had issues/defects during tests on a Chroma station.
Hence why only reviews of the 750W one are showing up for now.
I would like to see a review
I would like to see a review of the Seasonic Prime 1000W Platinum PSU once it’s available.