Article number: BN257



Proven Reliability and Good Efficiency

be quiet! System Power B8 350W (bulk) is especially designed to suit the needs of price-conscious PC builders. It features true be quiet! reliability and quietness with two 12V-rails and rock-solid voltages. System Power B8 350W is certified 80PLUS® efficient and supports GPU cards with one PCIe connector. It meets the latest Intel C6/C7, ErP and Energy Star guidelines and comes with a full suite of essential safety features.

System Power B8‘s combination of power, quietness, features and efficiency is letting you build cost-effective systems with good performance—a key differentiator in these days of identical commodities.

  • 350W of continuous power and two 12V-rails ensure rock-solid voltage stability
  • 80PLUS® certification and up to 87% power conversion efficiency
  • Quiet operation for its class achieved by an array of careful optimizations, including the use of a quiet 120mm fan
  • Production-optimized thanks to convenient bulk packaging
  • Product conception, design and quality control in Germany


  • Full suite of top safety protections defends against over-currents, over- and under-voltages, short circuits, overheating and overloads, thus safeguarding your valuable components
  • Two independent 12V-rails improve power signal stability
  • One PCI express connector for GPU card support
  • Compatible with 230V AC power mains

Energy Efficiency

  • 80PLUS® certification means operating efficiency for its class of up to 87%
  • High efficiency means cost savings, reduced heat wastage and overall quieter operation
  • Standby drain of less than 0.14 watts
  • Meets Energy Star 6.0 guidelines
  • Fulfills ErP 2014 guidelines
  • Zero Load design supports Intel®’s Deep Power Down C6/C7 mode

Quiet Operation

  • High-quality 120mm fan is thermally controlled to strike the best balance between proper cooling and quietness
  • Efficient PSU design produces low operating temperatures

Outstanding Service and Support

  • 3-years manufacturer's warranty
  • Production-optimized bulk packaging
  • Quick support is available via our international hotline, Mondays to Fridays from 9:00am to 5:30pm CET:
    +49 (0) 40-736 76 86 - 98


All models at a glance:


General data

Model System Power B8 | 350W
Continuous power (W) 350
Peak power (W) -
Form factor ATX 12V Version 2.4
Form factor EPS 12V -
Modular cable management -
Topology -
Wire-free design (DC-side) -
Voltage (Vac) 200 - 240
Frequency (Hz) 50
Input current (A) 3
PFC active
Power factor at 100% load >0.98
Compliant to Intel C6/C7
Power consumption in standby (W) 0.14
Average life time (h / 25°C) 100.000
Operating temperature up to (°C) 40


open all / close all


12V rails (multi-rail operation) 2
12V single rail operation -
Overclocking key -
+3.3V (A) 19
+5V (A) 15
+12V1 (A) 20
+12V2 (A) 16
+12V3 (A) -
+12V4 (A) -
+12V5 (A) -
+12V6 (A) -
-12V (A) 0.3
+5Vsb (A) 2.5
Max. combined power 12V (W) 324
Max. combined power 3.3V + 5V (W) 103
Hold-up time (ms @ 100%) 18ms (@ 75% load)

Fan / Cooling technology

Fan type high-quality fan
+SilentWings -
Motor technology 4-pole fan motor
Bearing technology Sleeve
Fan size (mm) 120
Max. fan speed (rpm), temperature-dependent 1,650
Temperature control for case fans -
dB(A) at 20% load 12.1
dB(A) at 50% load 12.3
dB(A) at 100% load 24.9


OCP (over current protection)
OVP (over voltage protection)
UVP (under voltage protection)
SCP (short circuit protection)
OTP (over temperature protection)
OPP (over power protection)

Safety certification

Nemko (N) -
Semko (S) -
Fimko (FI) -
Demko (D) -
cRUus -
cTUVus -
RCM (Australia)
CU (Russia)

Eco / Efficiency

80PLUS certification 230V EU internal
Efficiency (%) at 230V, 20% load 84
Efficiency (%) at 230V, 50% load 87
Efficiency (%) at 230V, 100% load 84

Environmental directives


Cable management / Connectors

Multi-GPU ready -
Modular cable management -
Fully modular -
Sleeved cables -
Flat cables -
Cable length to mainboard (cm) 45
Cable length to first connector (cm) 40
Maximum cable length (cm) 85
All-in-one cable (SATA/PATA/FDD) -
No. of cables 5
ATX-Motherboard (20+4-pin) 1 (24-pin)
P8 (CPU) -
P4+4 (CPU) 1
P4 (CPU) -
PCI-E 6-pin (GPU) -
PCI-E 6+2-pin (GPU) 1
PATA 4-pin 2
SATA 15-pin (HDD, Drives) 4
FDD (Floppy) -
External fan connectors -


Dimensions without cable (L x W x D), (mm) 140 x 150 x 86
Weight (kg) 1.60
Color -


Thumb screws -
Screws -
Cable ties -
Velcro cable ties -
Box/Bag for PSU/Cables -
User manual languages -
OCK slot bracket with switch / OCK jumper -
SFX-to-ATX adapter bracket -


Warranty (Years) 3
Express replacement service in first year -
International hotline / free of charge ✓ / DE, FR

Logistics data, RRP

Article number BN257
EAN code 4260052184523
Dimensions, package (L x W x H), (mm) -
Gross weight, package (kg) -
Pieces per packaging unit 10
Dimensions, shipping box (L x W x H), (mm) 545 x 525 x 195
Gross weight, shipping box (kg) 18.3
RRP (€) -

SYSTEM POWER B8 | 350W bulk
Article number: BN257