Our load tests utilize a couple of FAST ATE active load testers and a variety of other equipment such as an oscilloscope, power conditioner, temperature probe and a power consumption meter. You can read more about our standard testing approach here.
The tests performed are based around six conceivable setups that are out there and progressively load down the PSU up to the power supply's limits or 1000W, whichever comes first. Since our test equipment's limits are higher than that of the Thermaltake Toughpower DPS-850 850W power supply, we can test it to the maximum.
The above tests represent typical loads that we have measured from various systems and are meant to give a rough idea of where your computer might fall in line with our tests. Please keep in mind that each system is different and actual loads can vary greatly even with similar hardware.
Let's start by taking a look at the voltages to see how well this unit did during testing. Starting with the 12V rail, we see 2% regulation from start to finish with a total drop of .13V. The 5V rail managed to stay within 2% of specification with a total drop of .05V from start to finish. Moving towards the 3.3V rail, we see that regulation was within 2% of specification with a total voltage drop of .05V.
DC Output quality for the Thermaltake Toughpower DPS-850 850W was great and well within specifications. During Test 1, we saw 10mV of noise on our scope. When we increased the loads in Test 3, the ripple climbed to 19mV at a little over half load. During Test 5 under a load of 850W, the oscilloscope showed a maximum of 28mV on noise on the 12V rail.
The Thermaltake Toughpower DPS-850 850W is rated for 80 PLUS Gold efficiency. This means that the power supply must perform at 87%/90%/87% efficiency at 20%/50%/100% loads respectively. As you can see, the DPS-850 passed on our bench, and wasn't close to failing at any point.
For the first time since Corsair introduced digital power supplies to the consumer market a year ago, we now have some competition on the market. Thermaltake knew that they would have to bring their A-game to the plate if they were going to attempt to compete with what Corsair has to offer. They've done quite a good job of this just by looking at the power supply without the software.
As far as performance goes, the DPS-850 does very well. Voltage regulation just barely misses the 1% mark across the board, with all three rails showing within 2%. DC output quality is also very strong, staying under 30mV even at full load. Finally, the efficiency is great for a Gold rated power supply.
This may sound all sunshine and roses, but the problem is that the Corsair AX860i does everything the DPS-850 does and it does it better. Voltage regulation, DC output quality and efficiency are all better. Making things even worse is that it is cheaper and has been on the market for almost a full year.
Even with this being said, the Thermaltake DPS software helps offset this some, as it is much more polished that what we've seen so far from Corsair. Expect the second part of this review soon when we cover the DPS software. Until then, take the DPS-850 for what it is... a great power supply with a bit of a hefty price tag.