be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review

be quiet!'s Straight Power 11 Platinum 1200W ATX PSU goes under our spotlight. Should you buy it? Let's see.

Published
Updated
Manufacturer: be quiet! (BN645)
11 minutes & 6 seconds read time
TweakTown's Rating: 93%
TweakTown award

The Bottom Line

be quiet! has pulled off an aesthetically beautiful supply with the Straight Power 11 Platinum series. The performance and silence is substantial, but marred by a lack of small creature comforts and an unfortunate warranty.

Introduction, Specifications, and Pricing

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 01

be quiet! is a brand that is well known for making solidly built, and silence focused chassis for enthusiasts' PC builds. They also offer coolers, which you have likely seen in TweakTown reviews, but one area we have not dug into very much is their power supply offerings. This changes today as we have the newly released Straight Power 11 Platinum in hand for testing.

The straight Power 11 Platinum series is designed to be a high output supply without sacrificing efficiency or audibility. The platinum efficiency rating means that the PSU should have an optimal efficiency of 93%+, and the use of a Silent Wings fan ensures that noise levels should not be much of an issue.

The key features that be quiet! has listed for the Straight Power 11 Platinum is as follows:

  • 80 PLUS Platinum efficiency (up to 93.9%)
  • Virtually inaudible Silent Wings 3 135mm fan
  • Funnel-shaped fan opening of the PSU case for high airflow intake
  • Wire-free inside the PSU on the DC side for enhanced cooling and longevity
  • Modular cables for maximum build flexibility
  • Powerful multi-GPU support with six PCI-Express connectors
  • Japanese 105�C-rated capacitors ensure stability and reliability
  • ErP and Energy Star 7.0 ready
  • 5-year manufacturer's warranty

The one shocker here would be the five-year warranty. Presently the market for high-end PSU has a standard of ten-years for the warranty length for most power supplies. I have seen some models which are more mainstream buck this trend but a supply at the level of the Straight Power 11 Platinum, it is a bit surprising to see that they opted for half the duration. I can only assume this is to limit the liability for replacement to be quiet! and not an indicator of quality, or at least we hope. This decision will lose them some value points in my book as users do not have that sense of security that a substantially longer warranty allows.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 55
be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 56

The Straight Power 11 Platinum has a part number (article number) of BN645, which is not the most straightforward way of doing part numbers, but it is simpler than some I have seen. The use of article numbers with German manufacturers is something I am a bit familiar with, as Alphacool does the same thing. That being said, the Straight Power 11 Platinum measures in at 170mm in length, which means that some tighter cases might not work so well with it. However, needing a 1200W supply would in my mind mean you likely necessitate a larger chassis as well to fit the parts you will be powering, but it is worth noting as it is larger than some chassis will fit comfortably when fully equipped.

The price for the Straight Power 11 Platinum is a bit of a strange egg to crack as be quiet! does not set an MSRP, they set an SRP or suggested Retail price, which is $249.90 with notations that USA price may vary. This could be partially due to the Tariff or other issues. When checking online for availability, we find that the 1200W unit we are testing today is found on Amazon at $271.44, while the 1000W unit is listed for $249.50. So, for this review, we will be comparing the 1200W unit we are testing at the listed price of $271.44 when considering that price point for the fully modular platinum units that exist.

Looking at the options at this price point and one that caught my eye is the Seasonic Prime 1300W at $282.99, so with that considered, the rest in the price bracket we can find available are 1000w units around $255. The only other competition at this price range is the HX1000i, which is platinum and fully modular; however, it is 200W rated capacity short with a list price of $284.99.

Shannon's Power Supply Test System Specifications

Packaging

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 01

The packaging for the Straight Power 11 Platinum is standard for be quiet!. They carry a similar design ID to what we have seen on their cases. They include plus marks with the features integrated into the unit. I do like that the iconography is minimal, and be quiet! in standard fashion keeps things relatively simple.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 02

The rear of the package, even though it has four feature sections, still carries quite a clean aesthetic. The features displayed have text in both English and German.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 03

Flipping to the side of the box, we see that there is a QR code where you can go to the be quiet! website to learn more about the product. This will be helpful if you are in a shop looking at the PSU and want more information than the snippets offered on the packaging. I do like that be quiet! even lists that the QR code is for more details on this supply, and they translate that note into ten languages, including English.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 04

Spinning the package around to the thin opposite side, we find more information. We have the output table near the lower portion along with the array of safety and compliance iconography. The top is a small marketing blurb that tells the story of be quiet! and what their goal is.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 05

Opening the package and wee sitting atop the supply is the multi-page booklet style manual. The Supply is wrapped in a bubble wrap bag, and the cables are in two bundles under the cardboard flaps on each side of the supply.

Hardware & Documentation

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 07

The cables come in two bundles with a Velcro strap per bundle.

  • Main AC input cable
  • 24-pin ATX cable
  • 2x EPS CPU power cables
  • 3x dual 6+2 GPU PCIe Cables (six total 6+2 connectors)
  • 11x SATA power connectors
  • 4x PATA power connectors
  • PATA to FDD adapter
  • 4x zip ties
  • 4x PSU mounting screws

This cable array is adequate for the wattage that it is rated for. One thing I notice is that the PCIe connectors are limited to six in total, which is quite good as it will restrict the total expansion to something that should be safe or at least mostly safe from overloading. But in the words of Dr. Ian Malcolm, Life finds a way, and so do I... So, expect I will do my best to find the limits of this new PSU once we get to the real-world testing.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 06

The manual is a multi-page booklet, and it helps to explain the PSU capabilities and features for the entire Straight Power 11 Platinum lineup. This book may look rather large, but keep in mind that the data applies to six total PSUs.

Straight Power 11 Platinum 1200W Power Supply

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 08

The PSU, as previously mentioned, comes in a bubble wrap bag, which helps to keep the unit from damage during shipping. Usually, higher-end supplies invest in a sort of fancy bag and packaging for the PSU cables and the supply unit itself. However, be quiet! did not bother with any of that, so any excess cables will need to be bundled and stored however you see fit. I would like to see a better solution form be quiet! that users can utilize for storage of excess cables, as very few users will install the components necessary to need every cable installed.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 09

Opening up the supply, we take a look at the grille first. This is something special as be quiet! chose a very artisan look with bars running the length of the supply's fan opening to protect the fan itself from accidental intrusion. The metal bars feel very reminiscent of an art piece or maybe headers on a supercar. I know I'm getting lost in the weeds for a PSU fan grille, but I do feel like it is truly a well-made and well-integrated piece. Here we can also see the 135mm silent wings fan, which is similar to the fans we use on our PSU real-world testbench systems radiator for CPU cooling.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 10

Flipping to the first visible side and we see the specification label, which is a bit different than we are used to. Usually, the label is on the side opposite the fan, but be quiet! opted for a side mount, which will be visible if your chassis has no PSU shroud or a window here. I think I would have rather seen the stamped in be quiet! name here as it is more aesthetically pleasing.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 11

Here we see the section opposing the fan, which is where we would generally see the main label. This area is now a blank slate, which may be favorable for a system without a PSU shroud in place as it is solid black. I still do have mixed feelings on this and feel that for aesthetic purposes, the top bale is better than the side as that is what you will see for the most part through a window side panel.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 12

Here we have the other thin side, which is opposite the label side. This is the indented be quiet! logo I mentioned previously. I do like this aesthetic as it is subdued enough not to be considered pretentious, but it still shows your branding.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 13

Here we have the input side of the supply, and it is where we find the main AC input receptacle. Also, here is the mains toggle with eth decal above noting it can support from 110-240Vac input. Unlike several we have seen, be quiet! opted to make the area around the AC input and the mains toggle to be solid, while others open these areas up with mesh venting to allow airflow for cooling the PSU.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 14

Here we have a peek at the modular output connectors for the Straight Power 11 Platinum, and I like how this is arranged. While I like the simplicity of some of the dual 6+2 connectors for PCIe, I do like the current capability and inherent stability offered by direct cables. be quiet! has accomplished direct connections by having double 6+2 pins, which all get direct cabling from the supply via the 12-pin connectors. This means no pigtail off of the 6+2 for a second one off of the same lead. The motherboard is a split lead with a large portion to the right and a smaller pigtail next to the PCIe 3 connector. I do like that be quiet! has the proper amount of modular connections to support all of the cabling supplied in the package, not that most users would ever be able to populate them all with components.

Real World Test System & Observations

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 15

The first setup we run is with an edge overclocked 2990WX allowing for more amperage pull from the EPS connectors. This also ensures we can pull more overall load form the supply. First up with the TITAN V in place, we observed a load of between 740-770W during workstation loading for several hours. Much to my surprise, we observed temps of 46C from the PSU at what would around 60% loading.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 16

Next up, we added a 1080 Ti to the mix, and the load we were able to achieve was right around 970-1040W during a constant workstation loading. The workloads ran and did not see a single hiccup or output failure indicative of instability. The temp is now north of 50C, seeing a peak of 52 C where it bounced between 50 and 52 during loading. This is not bad but not ideal, and I know the PSU still has more in it, so we're going to turn up the wick a bit.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 17

Here we added a TITAN RTX to the testbench, and we observed a maximum wattage draw of 1215 - 1305W. Much to my surprise, the fan being ramped held the supply to a maximum peak of 53C while most time bouncing between 50-52C. The thermal management on the Straight Power 11 Platinum is excellent as it is one of the quietest supplies I have tested to date, especially when at full load. I would have loved to push it further, but with only three GPUs worth of cables, I stopped here as the PSU has done its job for several hours and did not even break a sweat it seems.

Final Thoughts

When be quiet! reached out to ask me to check out the Straight Power 11 Platinum supply, I was interested to see what be quiet! can do to differentiate itself from the pack. I feel that aesthetically be quiet! made some great choices, especially with the grille that you will likely never see. The labeling, I think, was a bit of a slip, but if it's under a PSU shroud, it may be of no consequence.

be quiet! Straight Power 11 Platinum 1200W ATX Power Supply Review 17

What we like

The Straight Power 11 Platinum series is merely beautiful. The quality of build and materials is excellent, and among the best, I have seen to date. The grille alone is something that is simply put, beautiful, and while, for most, it will be hidden forever, it creates a special feeling when you first open it up and see it. The ability to barely break into the 50's under an insane load is awe-inspiring and speaks to the engineering that be quiet! has done with this unit. The silence of the cooling is impressive, and I stand by the fact that I believe it is one of the quietest I have had the chance to test thus far. The side by side PCIe cabling is great and allows direct cabling form PSU to GPU with no pigtails to muck things up. The all-black wiring is also lovely but expected at this price point.

What do we think could be better?

The things I don't like will partially be my personal feelings, along with a comparative analysis of what I have seen on the market. First up is the lack of a way to store excess cabling. I know this may seem like a severe knit pick; at the price point, I do think users expect a certain level of presentation, like something like Apple, which is widely considered the gold standard of packaging designs. The application of the label on the side, which would be visible through the main window panel if there is no shroud, I feel is a weird choice, especially when you consider the opposing side has the embossed be quiet! name, which would look far better.

I cannot say 100% without cutting out the back panel, but I do wonder if cooling would be better if the area around the mains toggle and AC input receptacle were opened up with metal mesh-like the rest of the rear to allow better exhaust flow. One more point and probably one of the worst for be quiet! and this supply is its warranty, five-years is half what most other supplies at this level offer, and that will likely be a stumbling block for some.

For the price be quiet! demands, I do think be quiet! still has a competent unit. I do believe some of the small quality of life improvements would make for a better overall reception by users, but the unit delivers what it should and is as good as others if not better in its price category. The Straight Power 11 Platinum 1200W gets a solid recommendation from me, as it delivers a reliable experience with good thermals and little to no noise. Just be mindful of the shorter warranty, should something ever happen. This is why it fell just short of achieving an editor's choice or gold.

Shannon's Power Supply Test System Specifications

Photo of product for sale

Performance

98%

Quality

99%

Features

80%

Value

93%

Overall

93%

The Bottom Line

be quiet! has pulled off an aesthetically beautiful supply with the Straight Power 11 Platinum series. The performance and silence is substantial, but marred by a lack of small creature comforts and an unfortunate warranty.

TweakTown award

Shannon started his PC journey around the age of six in 1989. Now till present day, he has established himself in the overclocking world, spending many years pushing the limits of hardware on LN2. Shannon has worked with design and R&D on various components, including PC systems and chassis, to optimize the layout and performance for enthusiasts.

Newsletter Subscription
We openly invite the companies who provide us with review samples / who are mentioned or discussed to express their opinion. If any company representative wishes to respond, we will publish the response here. Please contact us if you wish to respond.