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

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Performance, Value, Noise and Efficiency

Performance Rating

The following graph shows the HPT650M’s total performance rating, comparing it to other units we have tested. To be more specific, the tested PSU is shown as 100 percent, and every other unit's performance is shown relative to it.

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The HPT650M falls well behind the 80 PLUS Gold-rated RM650x, while its deficit compared to the SSR-650PX is even larger. This platform needs an overhaul if FSP hopes to match the competition.

In the meantime, the only way to improve the HPT650M's position is with a better price.

Performance Per Dollar/Pound

The following chart may be the most interesting to many of you because it depicts the product’s performance-per-dollar score. We looked up the current price of each PSU on popular online shops and used those prices and all relative performance numbers to calculate the index. Note that all of the numbers in the following graph are normalized by the rated power of each PSU.  

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At the time this review was written, FSP's HPT650M was selling for $110, while Corsair's RM650x was available for $120, making it just $10 more expensive. The SSR-650PX and 650 G3 were selling for $110, too. That's an imposing group for FSP to battle on the basis of value.

Prices in the UK are quite a bit different, affecting our performance per pound chart.

Noise Rating

The graph below depicts the cooling fan's average noise over the PSU's operating range, with an ambient temperature between 30°C and 32°C (86°F to 89.6°F).

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This is a quiet power supply. When it comes to noise, our measurements put the HPT650M ahead of Seasonic's SSR-650PX.

Efficiency Rating

The following graph shows the PSU's average efficiency throughout its operating range, with an ambient temperature close to 30°C.

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FSP's platform is efficient, closely following the rest of its 80 PLUS Platinum- and ETA-A-rated competition.

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Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.