Thermaltake Toughpower 750 W (W0116RU) Power Supply
By Gabriel Torres on August 29, 2006
Toughpower 750 W is today the most high-end power supply from Thermaltake and they are going to release very soon 850 W, 1,000 W and 1,200 W models on this very same series. This model, internally called W0116RU, features a modular cabling system, a big 140 mm fan, is EPS12V-compatible and should deliver more power than any regular user needs, being targeted to SLI and CrossFire systems. Let’s take an in-depth look at this power supply.
Being a high-end power supply, Toughpower 750 W features high-efficiency and active PFC. According to Thermaltake this power supply has an efficiency up to 85% (compare to 50% to 60% on regular power supplies), meaning less power loss – an 85% efficiency means that 85% of the power pulled from the power grid will be converted in power on the power supply outputs and only 15% will be wasted. This translates into less consumption from the power grid (as less power needs to be pulled in order to generate the same amount of power on its outputs), meaning lower electricity bills.
Active PFC (Power Factor Correction), on the other hand, provides a better usage of the power grid and allows this power supply to be comply with the European law, making Thermaltake able to sell it in that continent (you can read more about PFC on our Power Supply Tutorial). In Figure 1, you can see that this power supply doesn’t have an 110V/220V switch, feature available on power supplies with active PFC.
This power supply uses a very good cooling solution. Instead of having a fan on its back, its fan is located at the bottom of the unit, as you can see in Figure 1 (the power supply is upside down). A mesh replaced the back fan, as you can see. Since the fan used is bigger than fans usually used on power supply units – even bigger than big fans used by power supplies using the same system: 140 mm –, this unit is not only quieter than traditional power supplies, but also provides a better airflow.
In Figure 3, you can see this power supply modular cabling system, used by its peripheral cables. In Figure 4, you can see the peripheral cables that come with this unit.
This power supply comes with two peripheral power cables containing four peripheral power connectors and one floppy disk drive power connector each, two Serial ATA power cables containing three SATA power connectors each, two PCI Express auxiliary power cables for your SLI or CrossFire video cards and one ATX12V/EPS12V cable. All these cables are connected to the modular cabling system and use a plastic sleeving, which helps with the PC internal airflow.
This power supply also has two cables connected directly into it, the main 20/24-pin power supply connector and another PCI Express auxiliary connector. Thus you can connect up to three video cards directly to this power supply without the need of any sort of adapter.
As mentioned this power supply uses a 24-pin motherboard power cable that can be easily transformed into a 20-pin one, see Figure 5. Its EPS12V connector can be also transformed into an ATX12V connector, see Figure 6.
Talking about its main power cables, we found a small aesthetic flaw. They use a plastic sleeving to keep all their wires together thus helping the PC internal airflow. This plastic sleeving, however, doesn’t go all through the way inside the power supply housing, so you can see a bunch of unprotected wires coming out of the power supply housing, see Figure 7.
On the other hand this power supply comes with a rubber protection for its rear, being the first time we’ve seen such feature.
The gauge of all main wires is 18 AWG.
We decided to fully disassemble this power supply to take a look inside.
We decided to disassemble this power supply to see what it looks like inside, how it is designed, and what components are used. Please read our Anatomy of Switching Power Supplies tutorial to understand how a power supply works and to compare this power supply to others.
In this page, we will have an overall look, while in the next page we will discuss in details the quality and rating of the components used.
We can point out several differences between this power supply and a low-end (a.k.a. “generic”) one: the construction quality of the printed circuit board (PCB); the use of more components on the transient filtering stage; the active PFC circuitry; the use of a thermal sensor on the power diodes heatsink for controlling the fan speed and for shutting down the power supply in case of overheating; the power rating of all components; the design; etcetera.
On Figures 9 and 10 you can have an overall look from inside this power supply.
Several funny things caught our attention inside this power supply. The most obvious was the use of this funny green tape everywhere (see Figures 9 and 10). We also found out that this power supply isn’t manufactured by Thermaltake, but by a company called CWT. In fact it looks like that Toughpower 750 W is actually a CWT PSH750V-C01 power supply. We found “Model: PSH750V” written on this power supply label, which corroborates our guess.
Is this a problem? Not necessarily, as several other well-known “manufacturers” are doing the same thing. The big question is: does this power supply use a good design? That’s exactly what we’ll try to answer.
Another funny thing about this power supply is that half of its 140 mm fan is covered with a transparent plastic, as you can see on the right in Figure 12. The part that is covered is the one above the rear part of the power supply, near the mesh found on the power supply’s rear.
As we mentioned on other articles, the first place we look when opening a power supply for a hint about its quality, is its filtering stage. On generic power supplies this stage has only one coil, two ceramic capacitors, one or two metalized polyester capacitors and, if we are lucky, one MOV (Metal-Oxide Varistor).
This power supply from Thermaltake uses one MOV, four ceramic capacitors, two metalized polyester capacitors and three ferrite coils.
On this stage we found another funny thing, a wire connected to ground cut and insulated with green tape, see Figure 13. Go figure.
We found more funny stuff here. The input filter is connected to the rectifying bridge using two wires (brown and blue wires with a red arrow on the left side in Figure 14), while on other power supplies this connection is done simply using traces on the printed circuit board. In Figure 14 you can also see that this power supply uses a very unpractical fuse holder.
In the next page we will have a more detailed discussion about the components used in the Toughpower 750 W.
We were very curious to check what components were chosen for the power section of this power supply and also how they were set together, i.e., the design used. We were willing to see if the components could really deliver the power announced by Thermaltake.
From all the specs provided on the databook of each component, we are more interested on the maximum continuous current parameter, given in ampères or amps for short. To find the maximum theoretical power capacity of the component in watts we need just to use the formula P = V x I, where P is power in watts, V is the voltage in volts and I is the current in ampères.
Keep in mind that this doesn’t mean that the power supply will deliver the maximum current rated for each component as the maximum power the power supply can deliver depends on other components used – like the transformer, coils, the PCB layout and the wire gauge – not only on the specs of the main components we are going to analyze.
For a better understanding of what we are talking here, please read our Anatomy of Switching Power Supplies tutorial.
This power supply uses one GBJ1506 rectifying bridge in its primary stage, which can deliver up to 15 A (rated at 100° C). This component is clearly overspec'ed: at 115 V this unit would be able to pull up to 1,725 W from the power grid; assuming 80% efficiency, the bridge would allow this unit to deliver up to 1,380 W without burning this component. Of course we are only talking about this component and the real limit will depend on all other components from the power supply.
Four power MOSFET transistors are used on this power supply primary, two on the active PFC circuit and two on the switching section. On the active PFC circuit two SPW20N60C3 are used, see Figure 15. These transistors have a maximum rated continuous current of 13.1 A at 100° C each (62.1 A in pulse mode at 25° C).
On the switching section two IRFP460A power MOSFET transistors in two-transistor forward switcher configuration are used, and each one has a maximum rated current of 80 A in pulse mode, which is the mode used, as the PWM circuit feeds these transistors with a square waveform. In continuous mode they can deliver up to 20 A @ 25° C or up to 13 A @ 100° C (note the difference temperature makes). As you may have noticed we are now publishing the temperature spec of each component, as this will play a major role on our analysis. As you can see, the higher the temperature, the lower current semiconductors can deliver. We will discuss more about this later.
For a better understanding on the relationship between these transistors, we drew a simplified diagram of this section of Toughpower 750 W power supply, see Figure 17.
This power supply uses a CM6800 integrated circuit, which is an active PFC and PWM controller combo. It is located on a small printed circuit board shown in Figure 18.
This power supply uses four Schottky rectifiers.
The +12 V output is produced by two STPS60L45CW Schottky rectifiers connected in parallel, which can deliver up to 60 A each (30 A per internal diode, measured at 135° C). The maximum theoretical current the +12 V line can deliver is given by the formula I / (1 - D), where D is the duty cycle used and I is the maximum current supported by the rectifying diode (which in this case is made by two 30 A diodes in parallel). Just as an exercise, we can assume a typical duty cycle of 30%. This would give us a maximum theoretical current of 86 A or 1,029 W for the +12 V output. The maximum current this line can really deliver will depend on other components, in particular the coil used. This output is clearly overspec'ed.
The +5 V output is produced by one STPS40L45CW Schottky rectifier, supporting up to 40 A (20 A per internal diode, measured at 130° C). The maximum theoretical current the +5 V line can deliver is given by the formula I / (1 - D), where D is the duty cycle used and I is the maximum current supported by the rectifying diode (which in this case is made by one 20 A diode). Just as an exercise, we can assume a typical duty cycle of 30%. This would give us a maximum theoretical current of 29 A or 143 W for the +5 V output. The maximum current this line can really deliver will depend on other components, in particular the coil used.
The +3.3 V output is also produced by another STPS40L45CW Schottky rectifier. Doing the same math this output would have a maximum theoretical current of 29 A or 94 W.
Even though the +5 V line and the +3.3 V line have separated rectifiers, they share the same transformer output. So the maximum current both lines can deliver will depend a lot on the transformer.
In Figure 19, you can see the four power Schottky rectifiers used on the secondary section and also the thermal sensor located on the secondary heatsink.
This power supply +5VSB output (a.k.a. “standby power”) uses a SBL1040CT Schottky rectifier, which can deliver up to 10 A (5 A per internal diode, measured at 95° C).
In Figure 20, you can see Toughpower 750 W label stating all its power specs.
From the previous page we came with some maximum theoretical numbers for the +12V output (1,029 W), +5 V (143 W) and +3.3 V (94 W).
As we mentioned earlier the maximum current/power each line can really deliver will depend on other components, especially the transformer, the coil and the wire gauge used.
One interesting thing about this power supply is that Thermaltake didn’t state the maximum power for each individual output on the power supply label, what is really unusual. For the +12 V output, for example, they stated 18 A for each one of the four virtual rails. This translates into 216 W per rail or 864 W total – more than the maximum labeled power for this power supply. This number is below the maximum current the +12 V rectifiers can deliver anyway.
For the + 5 V output Thermaltake stated a 28 A maximum current, which translates to 140 W, while for the +3.3 V output the manufacturer stated a 30 A maximum current, or 99 W. On the label, however, Thermaltake says that the combined power of +3.3 V and +5 V outputs is of 180 W (since they are connected to the same transformer output).
+5VSB output is labeled as having a 3 A maximum power, meaning 15 W.
Unfortunately we don’t have the necessary equipment to make a true power supply review; we would need to create a real 750 W load to check if this power supply could deliver its labeled power or not.
Thermaltake Toughpower 750 W power supply specs include:
* Researched at Shopping.com on the day we published this First Look article.
Even though we found several unusual things inside this power supply, it uses high-end power rectifiers on its secondary stage, not only from a very good supplier (ST Microelectronics) but also carrying a maximum current and power rated far above the labeled power for this power supply.
Of course the maximum power a power supply can really deliver depends on other components as well, like the transformer, the coils, the electrolytic capacitors and even on the gauge of the wires used.
Unfortunately we don’t have the necessary equipment to make a true power supply review – we would need to create a real 750 W load to check if this power supply could deliver its labeled power or not.
Even tough the rectifiers are top notch, the maximum labeled power was measured at 25º C instead of 50º C like other good high-end power supplies. Why this is important? The higher the internal power supply temperature, the lower power it can deliver. You will never get 25º C inside a power supply; typical real-world values are found between 35º C and 40º C. So a power supply labeled at 25º C may not deliver its labeled power when running in the real world.
We also missed on this power supply label the individual power each output can deliver.
It was also interesting to see that this power supply isn’t manufactured by Thermaltake. It is actually a relabeled CWT PSH750V-C01 unit. Several power supply “manufacturers” are doing the same, simply relabeling models manufactured by others. Some manufacturers may be using other companies only to manufacture products that were really designed by them, which isn’t the case with Thermaltake.
This power supply provides features also present on other high-end power supplies, like high efficiency (meaning a reduction on your electricity bill), active PFC, modular cabling system and some protections. We say “some” because power supplies from other companies provide more protection levels, like undervoltage.
Its price seems to be right for its labeled power and features.