be quiet! Pure Power 13 M 1200W PSU Review (2026)

1. Introduction2. Bundle & Cabling3. External4. Internal5. Testing Methodology and Results6. Closing Thoughts7. View All Pages

be quiet! have already been quite active in 2026 and today we check out another one of their power supplies – the Pure Power 13 M. be quiet! are releasing six models in this series across various capacities, and we have the flagship 1200W model on our test bench. These power supplies are fully modular and both 80 Plus and Cybenetics Gold rated.

These new Pure Power 13 M power units are ATX 3.1 and PCIe 5.1 compatible and offer semi-passive cooling. be quiet! are offering a 10-year warranty and while they aren't made in Germany, they claim ‘product conception, design and quality control in Germany'. I doubt they mean they are checking every unit made in China in their offices in Germany later, but it's a point be quiet! want to push. Make of it what you will.

Overall pricing certainly seems quite competitive based on the chart we were sent above.

Product Features (from be quiet!'s marketing materials):

Compatibility and Convenience

• ATX 3.1 form factor with up to 5 PCIe connectors for current- and next-gen GPUs.
• Full PCIe 5.1 and PCIe 6+2 compatibility with both cables in scope of delivery.
• Handles massive power excursions.

Exceptionally Quiet Operation

• Pure Power 13 M is a semi-passive PSU, only cooled actively when necessary, for a quieter operation.
• Exceptionally silent 120mm be quiet! fan is temperature-controlled to strike the best balance between effective cooling and quietness.
• Airflow-optimized fan blades reduce turbulence, allowing for best-of-class quiet functioning with excellent airflow.

Engineering and Efficiency

• 80 PLUS® Gold certification means very high operating efficiency for its class of up to 94.4%.
• Advanced stability and voltage regulation thanks to LLC technology.
• Up to 1200 Watts of continuous power.
• Modular cable management for maximum flexibility.

Outstanding Service and Support

• 10-year manufacturer's warranty.
• Product conception, design and quality control in Germany.

We wouldn't expect anything else from be quiet!, it's a simple dark box with orange accenting. The front highlights the two Gold certification badges from both Cybenetics and 80 Plus. We did confirm with be quiet! about the gold badge as we know these units actually achieved Platinum certification with Cybenetics, and they said ‘the test sample [with Cybenetics] might [have] been an outlier and we want to represent the efficiency level honestly'. So there you go.

The rear of the box has some information along the top with the same Gold certification badges and an overview of the power output, along with a PCIe 5.1 badge.

be quiet! include a little user manual, cable ties, mounting screws and a power cable.

Cable quality seems really good, between 16-18 AWG gauge cables. The main 600W 12+4 pin PCIe cable is 16-24AWG.

The cable lengths all seem fine to me even for larger cases, and there are plenty to support a reasonably high end system with a 50 series GPU.

The overall footprint of the Pure Power 13 M 1200W is compact. It measures 160 x 150 x 86 mm.

The grille at the top of the power supply is very open, ensuring good airflow from the fan to the components underneath. We will take a closer look at the fan shortly.

One side of the PSU is home to the power switch and connector. A large vented panel is at the side to help aid airflow. This fan adopts a semi-passive zero RPM cooling system. We have seen many versions of this before – basically the fan will disable at lower loads and internal temperatures to keep the noise floor as low as possible.

The modular side of the unit is all labelled with the cable connectors mounted vertically.

The unit is able to deliver 100A on the +12V rail, with the +3.3V and +5V minor rails able to deliver 22A for a total of 120W.

be quiet! have adopted a 120mm Chinese fan marked ‘BQ QF2 12025 HS' rated at 12V, 0.37A for a maximum of 2,700 rpm. Hopefully it won't be hitting those speeds in the real world, but we will find out shortly. This is not a more expensive fluid dynamic bearing fan, just a rifle bearing unit. be quiet! fans are generally quite good, however.

This is a Channel Well Technology (CWT) OEM design that they worked on with be quiet! for these supplies. On the primary side this is an APFC, half bridge design with LLC resonant converter. Secondary side is synchronous rectification & DC-DC convertors. The main cap is from Chinese brand Teapo – just a mid-range capacitor, not a more expensive Japanese unit, and it's rated at 85C (420V 1100uF). Again I don't know if recent Teapo standards are any better than the earlier days, but it would be nice to see be quiet! using higher quality caps in their units. If cheaper brands can use Japanese caps at similar price points, so should be quiet!

Transient filter comprises 2x X caps, 6x Y caps, 2x CM chokes and a single MOV.

Filtering capacitors on the secondary side are almost all from Teapo with a few from Elite – another Chinese brand.

Correctly testing power supplies is a complex procedure and KitGuru have configured a test bench which can deliver up to a 2,000 Watt DC load.

We test ambient temperatures at 35C in our environment to greater reflect warmer internal chassis conditions. We test at 230V.

We use combinations of the following hardware:

• SunMoon SM-268
• CSI3710A Programmable DC load (+3.3V and +5V outputs)
• CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4)
• Extech Power Analyzer
• Extech MultiMaster MM570 digital multimeter
• Extech digital sound level meter
• Digital oscilloscope (20M S/s with 12 Bit ADC)
• Variable Autotransformer, 1.4 KVA

DC Output Load Regulation
Combined DC Load	+3.3V		+5V		+12V		+5VSB		-12V
	A	V	A	V	A	V	A	V	A	V
120W	0.90	3.33	0.92	5.03	8.95	12.11	0.50	5.01	0.20	-12.01
240W	1.63	3.33	1.63	5.03	18.46	12.10	1.00	5.01	0.20	-12.01
600W	3.00	3.33	3.12	5.03	46.74	12.09	1.50	5.01	0.30	-12.00
900W	4.01	3.33	4.07	5.03	70.82	12.06	2.00	5.01	0.30	-12.01
1200W	5.02	3.32	5.20	5.02	94.59	12.02	2.50	5.01	0.30	-12.01

Load regulation is very good across the rails.

Next we want to try Cross Loading. This basically means loads which are not balanced. If a PC for instance needs 500W on the +12V outputs but something like 30W via the combined 3.3V and +5V outputs then the voltage regulation can fluctuate badly.

Cross Load Testing	+3.3V		+5V		+12V		-12V		+5VSB
	A	V	A	V	A	V	A	V	A	V
1190W	4.0	3.33	3.0	5.02	88.0	12.03	0.2	-12.02	0.50	5.01
240W	19.0	3.32	22.0	5.00	2.5	12.12	0.2	-12.02	0.50	5.01

No issues with the cross load test.

We then used an oscilloscope to measure AC ripple and noise present on the DC outputs. We set the oscilloscope time base to check for AC ripple at both high and low ends of the spectrum. ATX12V V2.2 specification for DC output ripple and noise is defined in the ATX 12V power supply design guide.

ATX12V Ver 2.2 Noise/Ripple Tolerance
Output	Ripple (mV p-p)
+3.3V	50
+5V	50
+12V1	120
+12V2	120
-12V	120
+5VSB	50

Obviously when measuring AC noise and ripple on the DC outputs the cleaner (less recorded) means we have a better end result. We measured this AC signal amplitude to see how closely the unit complied with the ATX standard.

AC Ripple (mV p-p)
DC Load	+3.3V	+5V	+12V	5VSB
100W	13	17	20	10
200W	14	18	22	12
400W	16	18	24	14
600W	16	20	27	16
800W	18	21	31	18
1000W	18	22	33	19
1200W	19	22	35	20

This unit passes our ripple suppression tests without any issues as well. Not class leading, but pretty decent.

Efficiency (%)
100W	89.2
200W	92.5
400W	93.1
600W	93.6
800W	92.8
1000W	91.9
1200W	90.5

Efficiency is good overall, hitting around 93.6% at peak. This drops to 90.5% at full load. Close to Platinum levels.

We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components. Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635.

Today to test the power supply we have taken it into our acoustics room environment and have set our SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) one meter away from the unit. We have no other fans running so we can effectively measure just the noise from the unit itself.

As this can be a little confusing for people, here are various dBa ratings with real world situations to help describe the various levels.

KitGuru noise guide

10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refrigerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 Player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum

Noise (dBA)
100W	<28.0
200W	<28.0
400W	<28.0
600W	30.5
800W	32.8
1000W	34.3
1200W	37.4

Even though this is a rifle bearing fan, the overall performance is very good. It is loud at full load as the fan starts ramping around loads of 800 watts and higher. At 50% load (600W) it's very respectable, which is about the sort of power draw most typical systems would hit under load (unless you game with an RTX 4090 or RTX 5090).

Temperature (c)
	Intake	Exhaust
100W	35	37
200W	36	40
400W	38	43
650W	43	45
800W	45	51
1000W	47	54
1200W	50	57

The fan moves a high level of air around the case, so the temperatures are very good. The high levels of efficiency help as well.

The Pure Power 13 M 1200W is one of the latest additions to be quiet!’s refreshed power supply lineup. From a physical standpoint, it is very well finished, with a compact chassis and a generally high standard of build quality. The included cabling is neatly presented and feels robust, which helps reinforce the overall impression of a well-made unit.

From a technical perspective, performance is strong across the board. Although the box lists 80 Plus Gold and Cybenetics Gold certifications, Cybenetics has in fact awarded this unit a Platinum efficiency rating. When we queried this with be quiet!, they confirmed the Platinum result but explained that the product is marketed as Gold because the review sample may have performed slightly above the average production standard. Our own testing placed the unit close to Platinum efficiency as well, making this a somewhat unusual case of conservative positioning rather than optimistic marketing.

Electrical performance is solid. Ripple suppression, load regulation and overall power delivery all meet a high standard. While it does not displace the very best units on the market in these areas, there are no meaningful weaknesses to report. Cooling is handled by a rifle bearing fan which performs reasonably well, though it is not on the same level as the larger and more capable Pure Wings fan used in the Power Zone 2 1200W we tested previously

Pricing is expected to sit around the £200 mark in the UK, based on an MSRP of roughly $200 or €215 elsewhere. At this price point, the use of Taiwanese Teapo capacitors throughout the unit is more difficult to overlook. While modern Teapo capacitors are not inherently unreliable, and we are not suggesting they pose a durability risk under normal use, their inclusion does feel like a cost-saving measure that sits uncomfortably in a £200-plus power supply. Ideally, this would not be a discussion point at all at this level.

Pros:

• Fully modular.
• Technically capable.
• Well built.
• 10-year warranty.
• Strong load regulation.
• Ripple suppression is good.

Cons:

• Teapo caps in a £200 power supply.
• Fan quality falls short of what I would expect from be quiet!

KitGuru says: The be quiet! Pure Power 13 M 1200W delivers strong performance, good efficiency and a well-built, compact design. It runs quietly at lower loads, offers a long 10-year warranty and performs reliably under testing. While pricing and component choices prevent it from being class-leading, it remains a capable option worth considering.

Become a Patron!