FSP DAGGER PRO 550W SFX Power Supply Review

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DC Output Quality

For those of you that are curious as to some of the reasoning and equipment behind our PSU testing program here at TheFPSReview, we have put together an introduction for you that shares a lot of the behind the scenes of the program. This program is based on what the author developed at [H]ardOCP and utilizes the equipment bequeathed to the author by Kyle Bennett. The testing we are conducting today is exactly as described in that document and will continue with our examination of the DC Output Quality.

Control Test Graphing

This image is the blank background control test on an unused connector from our SM-8800 during the testing of the FSP DAGGER PRO 550W. This lets us determine what the background noise looks like during testing.

120v Input

100v Input

Test #1 is equal to approximately 25% of the rated capacity of the FSP DAGGER PRO 550W at 45c. This makes Test #1 equal to 148W by loading the 12v rail to 10a, the 5v rail to 2a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. The FSP DAGGER PRO 550W is starting off in active form. The 12v rail is peaking at ~60mV of ripple/noise while the minor rails are peaking at less than ~10mV of ripple/noise.

120v Input

100v Input

Test #2 is equal to approximately 50% of the rated capacity of the FSP DAGGER PRO 550W at 45c. This makes Test #2 equal to 277W by loading the 12v rail to 20a, the 5v rail to 3a, the 3.3v rail to 2a, the +5vsb to 2a, and the -12v to 0.3a. Test #2 sees no real changes on the minor rails as they are coming in at less than ~10mV of ripple/noise still. The 12v rail has seen its ripple/noise value halved as it is coming in at ~30mV of ripple/noise.

120v Input

100v Input

Test #3 is equal to approximately 75% of the rated capacity of FSP DAGGER PRO 550W at 45c. This makes Test #3 equal to 406W by loading the 12v rail to 30a, the 5v rail to 4a, the 3.3v rail to 3a, the +5vsb to 2a, and the -12v to 0.3a. Test #3 sees the same essential results as we saw in Test #2. The 12v rail is coming in at a peak of ~30mV of ripple/noise while the minor rails are coming in at ~10mV of ripple/noise.

120v Input

100v Input

Test #4 is equal to approximately 100% of the rated capacity of the FSP DAGGER PRO 550W at 45c. This makes Test #4 equal to 548W by loading the 12v rail to 40a, the 5v rail to 7a, the 3.3v rail to 5a, the +5vsb to 2a, and the -12v to 0.3a. In the final regular test, we see the 12v rail peaking at ~40mV of ripple/noise while the minor rails are peaking at ~20mV of ripple/noise on the 5v rail and ~10mV on the 3.3v rail.

Torture Test

The Torture Test is equal to approximately 80% of the rated capacity of the FSP DAGGER PRO 550W at 45C. This makes the Torture Test equal 445W by loading the 12v rail to 31a, the 5v rail to 8a, the 3.3v rail to 5a, the +5vsb to 2a, and the -12v to 0.3a. At the end of the Torture Test, we see the 12v rails peaking at ~30mV of ripple/noise while the 5v rail is peaking at ~15mV of ripple/noise and the 3.3v rail is peaking at ~10mV of ripple/noise.

DC Output Quality Summary

The overall DC Output Quality of the FSP DAGGER PRO 550W is passing. The DAGGER PRO 550W ended up posting a peak trace amplitude on the 12v rail of ~60mV followed by ~20mV on the 5v rail and ~10mV on the 3.3v rail. The worst relative value among these hit ~50% of the ATX12v specification limit which is not great. These results are mixed with the Bitfenix Formula Gold 550W mostly based on the performance of the 12v rail. So, while not necessarily amazing, this unit is at least competitive with ATX12v/EPS-sized units that we have seen to date while being a much smaller form factor. Let’s move on now and see how all of this wraps up!

Paul Johnson
Paul is a long time PC hobbyist and tech enthusiast having gotten his start when he broke his first C64 quickly followed by breaking his first IBM XT. Most notably however, for 12 years, he served as the Power Supply Editor for one of the truly early, groundbreaking, and INDPENDENT PC enthusiast sites ([H]ardOCP) until its mothballing in April of 2019. Paul now brings the same flair and style of his power supply reviews to The FPS Review.

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