Protection Features Evaluation

We have several issues here. OCP at +12 V is set too high. Practically, the PSU didn't shut down. I had to abort the test since ripple went through the roof and voltage dropped too low, which are signs of imminent failure. To make matters worse, OCP is also set too high on the minor rails for no apparent reason, especially at 3.3 V, where I applied a load of over 40 A load, which still didn't make OCP shut down the PSU!

On the other hand, OPP is set correctly, which is something at least. Moreover, there is over-temperature protection, but no surge protection since the PSU's platform lacks an MOV.

DC Power Sequencing

According to Intel's most recent Power Supply Design Guide (revision 1.4), the +12 V and +5 V rails must have voltages equal to or greater than the +3.3 V rail's output at all times. We turn the unit off for our first measurement and switch it back on without a load on any of the rails.



The 3.3 V rail is always lower than the other two rails.

EMC Pre-Compliance Testing - Average and Peak EMI Detector Results

Electromagnetic Compatibility (EMC) is the ability of a device to operate properly in its environment without disrupting the proper operation of other close-by devices.

Electromagnetic Interference (EMI) stands for the electromagnetic energy a device emits, and it can cause problems in other close-by devices if too high.


Four spurs go over the limit with the average detector, but everything is fine with the peak EMI detector.