BeQuiet Dark Power Pro 650W First Class review

Power Demand

Allow me to try and answer the big question most of you will have. Why these hefty PSUs ? Two-three years ago we all had 350 Watt power supplies where as 450 is now the standard entry level PSU. 550 Watt is pretty normal, and high-end starts at 650 Watt. But why do we need 650 Watts you ask ? Well; high-end gamers PCs these days need a good power supply unit (PSU). The power consumption that a PC can create these days is a little unheard of.

Increased transistor counts for processors (GPU/CPU) versus higher clock frequencies and most of all do not ignore the "Dual & Quad" trend. We have multi-core CPUs, and instead of one graphics cards we now have the option to double, triple or Quad up graphics power with cards in SLI or CrossfireX mode.

Though an extremely small percentage of PC consumers really makes use of such options, it is a trend and multi-GPU gaming and computing is up and coming.

Yet a current high-end rig (which we'll use to test this PSU today) averages at 400-500 Watts power consumption. Now you can see why these little old grey 300 Watt PSU's we had 3 years ago are by far not sufficient anymore.

Today for example with two GeForce 8800 cards in SLI, Core 2 Quad Q6600 processor overclocked and 2 GB memory we'll peak over 500 watts easily.

A PSU needs to manage the power demand in a very secure way otherwise it'll create instability throughout the system. That instability can result as crashes, freezes, underperforming software such as games that run poorly when the graphics card isn't fed enough power, and even resets or shuts down the system completely. Please do not underestimate the importance of the PSU.

Aesthetics

Two years ago another trend picked up which we did not foresee. We, the consumers, all created a demand for modified PCs. The dull beige painted PCs had to go. We want nicely shaped and cooled PCs, preferably lit with side windows, so we could actually look at the inside. Really cool to look at, but that created another issue. We now have the beautiful looking cases where you could look inside, but that resulted in pulling the hairs out of your head as there were yellow, red, and black wires coming from the PSU everywhere.

So the power supply received another function; aesthetics. It needs to look nice. By organizing cables and by giving you the option to actually modify the wires you want to use, another problem was solved. We call it cable management these days.

The two reasons mentioned above from a consumer point of view so far have been by far the most important development for PSUs. Namely stable high output quality power distribution and the option for modability, using only the wires that you need. Almost EVERY manufacturer has picked up on this trend and it has become a very big market for sure.

Sound slash noise levels

But yet another factor rises that we now need to weigh in. Sound levels coming from your PSU. The high rated PSU's typically have two fans and a lot of manufacturers did not pay attention to all the noise a PC makes these days. So the third factor was utilizing silent high-performance fans preferably with smart-fan technology (variable fan speeds based on heat).

Power Efficiency

Last but not least, the biggest trend in PSU development next to the looks, stability and noise levels has to be power efficiency.

But what does that mean? The Power Efficiency of a power supply? First and foremost; the higher the better, efficiency is good. When power is drawn from your wall socket and travels into your power supply, not all of it is transformed into electricity that your computer consumes. A rather large part of that current will get lost as there is heat that is dissipating in the capacitors or leakage in circuits and other losses. So it boils down to this: If your computer requires 500 watts of power, a power supply will draw more than that from your electric company. Here's an example:

If you have a generic older power supply with an average 70% efficiency a 350 power draw (350/70x100) watt load would mean it is drawing 500 Watts of current from your wall socket while your PC only uses 350 watts, interesting eh? Yes, you loose 150 Watts yet are paying for that loss.

Let's do that math again, yet this time with a 80% power efficiency in mind: 350/80x100= 438 Watt. So that's saving 64 Watts over a 70% efficient product. If you have your PC powered on a lot , think about this theory and what it can save you in the long term.

Now if we estimate that today's tested PSU has a 85%-87% efficiency 350/85x100=412 Watt. We just saved 88 Watts by simply opting for a better power supply.

Let's place that in a table:

	PSU Efficiency in % 350W baseline 70 500 75 467 80 438 85 412 87 402 88 398 89 393 90 389

The higher the efficiency the less power loss, the less money you have to pay. And hey ... it's good for mother nature as well. I find energy efficiency one of the most important developments in a PSU this and coming year, we'll monitor this closely. Some food for the brain, green is good:

Depending on your energy supplier, country of origin etc, you will pay approx 15p(UK)/€0.21(EU)/$0.30(US) per unit. A device using a kilo watt of power for one hour is a kWh or a unit of energy. At the moment we are seeing increasingly expensive energy costs in gas and electricity. So getting more efficient equipment, or going greener in general should actually save you money.

Keep this in perspective though, your 70% efficient 600W PSU which was probably cheap lets say €40 trying to pull 350W (so thats 500W in real terms). Compare that to a 87% PSU on test today €235 trying to pull the same 350W (thats approx 400W in real terms). 100W difference per hour is a cost difference of €0.021. To break even, we'd have to run these PCs continuously for 386 days / 9285 hours. If energy prices go up, obviously the time it takes to break even comes down.

Now judging from the specs the power efficiency of PSU is is nothing to be ashamed about either as it is rated at an 85%-87% measured at 230V (which we use here in Europe) and at 100% load it's energy efficiency should still be 83%.

So next to being a really capable, this is an efficient PSU.

Active PFC

This model has a very nice feature called Active PFC. To put it in simple terms, Active PFC PSUs are more expensive and, from a power consumption point of view, more efficient. Power Factor Correction (PFC) allows power distribution to operate at its highest efficiency. There are two types of PFC, Active PFC and Passive PFC. This PSU has Active PFC. Active PFC uses a circuit to correct power factor, Active PFC is able to generate a theoretical power factor of over 95%. Active Power Factor Correction also markedly diminishes total harmonics, automatically corrects for AC input voltage, and is capable of a full range of input voltage. Since Active PFC is the more complex method of Power Factor Correction, it is definitely more expensive to produce an Active PFC power supply.

Warranty

The PSU has a 3 year warranty quite nice. Alright ... let's have a look at the photo shoot followed by some testing.