FSP Hydro PTM+ 850W (Page 3 of 4) | Reports

Page 3 - Physical Look - Inside

As always, we opened up our FSP Hydro PTM+ 850W power supply to take a detailed look at what is going on inside. Please note that doing this at home will void your two-year warranty, thanks to the warranty seal FSP applied over one of the attachment screws. Not that you are missing much anyway -- two year is nothing when everyone else is offering warranties that are a decade or longer. FSP says since this is the first water cooled PSU in the market, the technology is less mature, hence the shorter warranty. For the benefit of you, we cracked ours open, so you do not need to. There are no user serviceable parts inside.

Disassembling the FSP Hydro PTM+ 850W is quite straightforward with the removal of four screws. Our photo above shows an overhead view of its internal components. Its OEM is, unsurprisingly, FSP themselves. At first glance, the build quality appears to be excellent. There are four main heatsinks inside. A medium and small heatsink are located on the primary side, both of which are painted black. Two unpainted smaller heatsinks can be found down the line, but no electronic components are attached to them. The Bitspower water cooling block covers the entire area below the PCB. Unfortunately, due to patents and trade secrets, we were not allowed to take apart the water cooling block or show any photos of it.

Pulling the enclosure apart and we got straight to the internal inspection. The transient filter stage is the first input stage of a computer power supply, so we will take a look at that first. FSP has always done a great job in the past to make sure their power supplies met or exceeded the recommended requirements, and the FSP Hydro PTM+ 850W is no exception. The FSP Hydro PTM+ 850W has one metal oxide varistor, two metalized polyester X-capacitors, five ceramic Y-capacitors, and two ferrite coils. This is two times the amount of X and Y capacitors than recommended. Considering some modern-day PSUs have missing MOVs, I am happy to see it here, as this component is used to stabilize spikes from the AC line.

The active PFC circuit featured on the FSP Hydro PTM+ 850W uses three Diodes Incorporated GBJ1506 bridge rectifiers in close array near the transient filter stage. At 115V, the maximum rectified forward current capacity with heatsink is 15A each, so you can theoretically pull up to 5175W (15A * 3 diodes * 115V) from the bridge rectifier at 100% efficiency. Of course, this is limited by the fact that it is not 100% efficient and also neglects the fact that not every component in the system are able to keep up. Further down the line, on the outside of the largest heatsink, we can see two Infineon IPW60R120P7 power transistors. Each is certified for up to 16A at 100c. These transistors present a maximum resistance of 0.120 ohm when turned on according to the manufacturer's data sheet. A Rohm Semiconductor SCS308AP SiC Schottky barrier diode is placed right next it. A Power Integrations InnoSwitch3 INN3674C flyback switcher IC MOFSET transistor is found in the Hydro PTM+ 850W power supply as well. Further down the line, there are two STMicroelectronics STF28N60M2 power MOSFETs. The 28N60M2's rated continuous drain current is 14A at 100c. It has an RDS(on) value of 0.150 ohm maximum and 0.135 ohm typical. This on characteristic is called Static Drain-Source On-Resistance, or commonly abbreviated as RDS(on). The more efficient the component is, the lower the RDS(on) value, since it wastes less power with lower resistance.

We can see two Japanese brand Nippon Chemi-Con capacitors and its dual transformer design in the photo above. 100% Japanese brand capacitors are specified on the marketing material, so this is to be expected. Our 850W version of FSP's latest Hydro-series power supply incorporates two 330µF x 420V capacitor in parallel for an equivalent capacitance of 660µF. It is rated at 105c; whereas more value-oriented power supplies usually use 85c rated capacitors.

In the middle, we can find a Silicon Labs Si8233BD dual isolated drivers chip and a Champion CM6901T2X resonant switching controller.

On the secondary side, we can see more Japanese brand capacitors from United Chemi-Con and Rubycon rated at 105c. As with modern high efficiency power supplies, all rectifiers produce the +12V out, while the +5V and +3.3V outputs are generated from the +12V output using a DC to DC converter within the power supply unit. Six Toshiba TPHR8504PL power MOSFETs are responsible for generating the +12V output, located at the back of the PCB on the water block for additional cooling, not shown. The TPHR8504PL's rated continuous drain current is 150A at 25c. It has an RDS(on) value of 0.0007 ohm maximum and 0.00085 ohm typical. An International Rectifier FR1018E is spotted at the back as well. Meanwhile, a Silicon Touch PS223 monitoring IC provides over/under current and over/under voltage protection. ANPEC's APW7159 is the synchronous buck PWM controller. The datasheets for all components mentioned in this review can be found on their respective manufacturer's websites.

At the back, we have a large daughterboard covering the entire rear panel for the modular cable sockets. All modular sockets at the bottom are soldered directly to the main PCB after the secondary stage. Copper bars join the mainboard and daughterboard to reduce power transmission loss. The output connector configuration can be seen on the previous page. Overall, the internal build quality of FSP's Hydro PTM+ 850W power supply is excellent -- something we would expect from an FSP built unit. Components are arranged very well for optimal cooling with minimal wires running around inside, and solder points on its black PCB is quite clean in general. I would say the FSP Hydro PTM+ 850W is generally very good with regards to the selection of components used under the hood; appropriate for its performance class.

Lastly, we see a 135mm fan that provides cooling to the FSP Hydro PTM+ 850W's internal components. It is connected to an add-in board using a 2-pin connector. A 135mm fan is only marginally smaller than the 140mm maximum you can fit in an ATX power supply, and it is beneficial in most cases in providing lots of airflow at lower speeds for quiet operation. Protechnic Electric is the fan OEM with MGA13512XF-A25 as the model number, as shown in our photo above. Further research indicates the MGA13512XF-A25 is a fluid dynamic bearing fan specified at 0.38A for a maximum of speed of 2300 RPM.


Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion