FSP Hydro PTM 650W PSU Review: Clean, Quiet Power for Mid-Range PCs

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Cross-Load Tests and Infrared Images

Our cross-load tests are described in detail here.

To generate the following charts, we set our loaders to auto mode through our custom-made software before trying more than 25,000 possible combinations with the +12V, 5V, and 3.3V rails. The load regulation 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 is between at 30°C (86°F) to 32°C (89.6°F).

Load Regulation Charts

Efficiency Chart

It is nice to see some of this chart reflecting >92% efficiency. The blue-colored region represents the 90-92% efficiency range, which is fairly large.

Ripple Charts

Infrared Images

We apply half-load for 10 minutes with the PSU's top cover and cooling fan removed before taking photos with our modified FLIR E4 camera that delivers 320x240 IR resolution (76,800 pixels).

Temperatures remain low thanks to FSP's efficient platform. The hottest parts are the VRMs responsible for regulating the minor rails; we push them especially hard during our tests.


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Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.