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|OCP (Cold @ 25°C)||12V: 94.6A (113.52%), 11.892V|
5V: 30.1A (136.82%), 5.011V
3.3V: 30.1A (136.82%), 3.292V
5VSB: 4.6A (153.33%), 4.904V
|OCP (Hot @ 40°C)||12V: 94A (112.80%), 11.896V|
5V: 29.7A (135%), 5.028V
3.3V: 29.4A (133.64%), 3.3V
5VSB: 4.6A (153.33%), 4.902V
|OPP (Cold @ 23°C)||1223.28W (122.33%)|
|OPP (Hot @ 37°C)||1223.44W (122.34%)|
|OTP||✓ (167°C @ 12V Heat Sink)|
|SCP||12V to Earth: ✓|
5V to Earth: ✓
3.3V to Earth: ✓
5VSB to Earth: ✓
-12V to Earth: ✓
Inrush: NTC Thermistor & Bypass relay
The OCP triggering points are correctly set at 12V and 5V. At 3.3V, although there are no ripple or load regulation problems, there is no need for so many Amperes. Over power protection is set correctly, and there is over temperature protection to shut down the unit if it is overheated.
DC Power Sequencing
According to Intel’s most recent Power Supply Design Guide (revision 1.4), the +12V and 5V outputs must be equal to or greater than the 3.3V rail at all times. Unfortunately, Intel doesn't mention why it is so important to always keep the 3.3V rail's voltage lower than the levels of the other two outputs.
No problems here since the 3.3V rail is always lower than the other two.
Cross Load Tests
To generate the following charts, we set our loaders to auto mode through custom-made software before trying more than 25,000 possible load combinations with the +12V, 5V, and 3.3V rails. The deviations in each of the charts below are calculated by taking the nominal values of the rails (12V, 5V, and 3.3V) as point zero. The ambient temperature during testing was between 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit).
Load Regulation Charts
The lower the power supply's ripple, the more stable the system will be and less stress will also be applied to its components.
We apply a half-load for 10 minutes with the PSU's top cover and cooling fan removed before taking photos with a modified Fluke Ti480 PRO camera able to deliver an IR resolution of 640x480 (307,200 pixels).
Without active cooling, the FETs that regulate the 12V rail get pretty hot, reaching 100 degrees Celsius. Nonetheless, these FETs can still handle up to 143A at this temperature. Moreover, the ZD502 diode on the vertical 5VSB board gets quite hot, at 104.55 degrees Celsius.
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Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.