be quiet! · Power Supply Unit

be quiet! System Power B9 price in United Kingdom

MPN BN209MPN BN206MPN BN207EAN 4260052186015EAN 4260052185988

Noise11.6 dB
Weight1.52 kg
ColourGrey
Total power300 W

Lowest price incl. delivery

£40.98

at Back to the OfficeIn stock

1 store
Range £40.98 – £62.99
Save up to £22.01 vs. the dearest store
1 in stock
1 with free delivery
Checked 6 Oct 2026, 05:40 UTC

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Full specifications and side-by-side comparison

Prices in United Kingdom

1 store · prices in GBP · updated 6 Oct 2026, 05:40 UTC

Lowest price£40.98at Back to the Office · incl. shippingGo to Back to the Office

Price range across 4 offers

Save up to £22.01 (35%) by choosing the cheapest store

1 of 1 stores in stock
1 with free shipping
Checked 6 Oct 2026, 05:40 UTC

Back to the OfficeLowest pricebe quiet! System Power B9 power supply unit 300 W 20+4 pin ATX ATX Grey In stock£4.99 shipping
£40.98£35.99 + £4.99 shipping
Go to store : Back to the Office (opens in a new tab)
Back to the Officebe quiet! System Power B9 power supply unit 350 W 20+4 pin ATX ATX Grey In stock£4.99 shipping
£43.98£38.99 + £4.99 shipping+£3.00 (7%) vs lowest
Go to store : Back to the Office (opens in a new tab)
Back to the Officebe quiet! System Power B9 power supply unit 450 W 20+4 pin ATX ATX Grey In stockFree shipping
£50.99incl. free shipping+£10.01 (24%) vs lowest
Go to store : Back to the Office (opens in a new tab)
Back to the Officebe quiet! System Power B9 power supply unit 600 W 20+4 pin ATX ATX Black In stockFree shipping
£62.99incl. free shipping+£22.01 (54%) vs lowest
Go to store : Back to the Office (opens in a new tab)

Ad: we may earn a commission when you buy through these links; it never changes the order, which is by total price only. Prices and stock are shown as each store states them, as of 6 Oct 2026, 05:40 UTC, and can change at any time. Taxes are included only where the store includes them.

Price history in United Kingdom

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Best price · Back to the Office£40.98

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Product details

Identification

Brand: be quiet!
Product: System Power B9
Full name: be quiet! System Power B9 power supply unit 300 W 20+4 pin ATX ATX Grey
Manufacturer part number: BN209, BN206, BN207, BN208
EAN / UPC: 4260052186015, 4260052185988, 4260052185995, 4260052186008
Category: Power Supply Unit

50 specifications from the manufacturer's data sheet

Power

Total power	300 W
AC input voltage	200 - 240 V
AC input frequency	50 Hz
Input current	2.5 A
Power factor	0.95
Power Factor Correction (PFC) type	Active
Combined power (+3.3V)	103 W
Combined power (+12V)	276 W
Combined power (+5V)	103 W
Combined power (-12V)	3.6 W
Combined power (+5Vsb)	12.5 W
Max output current (+3.3V)	17 A
Max output current (+12V1)	18 A
Max output current (+12V2)	14 A
Max output current (+5V)	15 A
Max output current (-12V)	0.3 A
Max output current (+5Vsb)	2.5 A
Efficiency	87%
Hold time	17 ms
Power protection features	Over current, Over power, Over voltage, Overheating, Short circuit, Under voltage

Ports & interfaces

Motherboard power connector	20+4 pin ATX
Motherboard power cable length	45 cm
Number of PATA power connectors	2
Number of SATA power connectors	4
SATA power cable length	400 mm
CPU P4 connector (4-pin)	1
CPU power cable length	45 cm
Cabling type	Non-Modular