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Transient Response Tests
Advanced Transient Response Tests
For details on our transient response testing, please click here.
Ιn these tests, we monitor the response of the PSU in two different scenarios. First, a transient load (10A at +12V, 5A at 5V, 5A at 3.3V and 0.5A at 5VSB) is applied for 200ms while the PSU works at 20 percent load. In the second scenario, the PSU is hit by the same transient load while operating at 50 percent load. In both tests, we use our oscilloscope to measure the voltage drops caused by the transient load. The voltages should remain within the ATX specification's regulation limits.
These metrics are crucial because they simulate the transient loads a PSU is likely to handle (such as booting a RAID array or an instant 100 percent load of CPU/GPUs). We call them "Advanced Transient Response Tests," and they are designed to be very tough to master, especially for PSUs with less than 500W capacity.
Advanced Transient Response at 20 Percent
Advanced Transient Response at 50 Percent
Voltage drops on the +12V rail are quite low. The same goes for the 5V and 5VSB rails.
The deviations aren't large at +12V. However, the low initial voltage during the second test leads to a reading below 3.2V when the transient load is applied.
Here are the oscilloscope screenshots we took during Advanced Transient Response Testing:
Transient Response At 20 Percent Load
Transient Response At 50 Percent Load
Turn-On Transient Tests
In the next set of tests, we measure the PSU's response in simpler transient load scenarios—during its power-on phase.
For the first measurement, we turn off the PSU, dial in the maximum current the 5VSB can output and switch on the PSU. In the second test, we dial the maximum load the +12V can handle and start the PSU while it's in standby mode. In the last test, while the PSU is completely switched off (we cut off the power or switch off the PSU by flipping its on/off switch), we dial the maximum load the +12V rail can handle before switching on the PSU from the loader and restoring power. The ATX specification states that recorded spikes on all rails should not exceed 10 percent of their nominal values (+10 percent for 12V is 13.2V, and 5.5V for 5V).
Everything is fine here; the spike in the last test is tiny and the voltage overshoot is small as well.
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Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.
I do not see anywhere the limitation regarding the need of Flash Active X 15 and only that, in order the PSU's software DPSapp to operate. Is there anything changed? I own one of its little brothers the Toughpower 550W and on my system the DPSApp refuses to run on an Active X version higher than 15.In fact on the download page there is a note sayingReply
"※Note: The Adobe Flash Player ActiveX 20.0.0 version or above might NOT be compatible DPS G PC App."
"※Note: The DPS G PC App requires Adobe Flash Player Version 126.96.36.1990 or above and Microsoft .NET Version 4.5 or above."
This is a wimpy power supply. Bring on 5 KW units!Reply
This is a wimpy power supply. Bring on 5 KW units!
:lol: It would be great for litecoining machines. :)
hm I am not aware of this flash/directX issue. In my system I just installed the DPSApp and it ran fine. I have all updates installed. However this App still needs work and they should abandon the flash platform IMO.Reply
18063833 said:hm I am not aware of this flash/directX issue. In my system I just installed the DPSApp and it ran fine. I have all updates installed. However this App still needs work and they should abandon the flash platform IMO.
In my case, I had no Flash on my system at all. I consider it dangerous and useless. But in order to operate DPSApp I first installed the latest version of Flash and the DPSApp crashes every time i try to open the GUI. Only on the v15 I manage to make it work. :sarcastic:
PSUs in the >1kW range should deliver at least 3.5A-4A on 5VSB.
Why? It is the standby power? What modern system needs more than 15W standby?
it isn't the system that needs it, but the devices that you might try to charge through 5VSB when the PSU is in standby.Reply
so, there is absolutely no reason to buy this over the aging AX1200i or even the not-as-fancy HX1200i... in fact, if you buy this unit you either live in a country where corsair PSUs are hard to get or you are a moron.Reply
it failed the hold up requirement, regulation and ripple is mediocre at best, it's hideous and single rail designs really need to go from PSUs this powerful. 100 amperes is enough to arc weld! if the DSP malfunctions and send 100 amps down your motherboard or GPU, it'll set your house on fire. this isn't really a problem with old school analog designs. but with anything digitally controlled, bugs are always a concern.
AX1200i is a way better performer in pretty much every metric, has a 10 year warranty these days, and individually sleeved cables are relatively cheap and readily available.