PC parts / Power supplies
MontechPower supply
Century II 850W
Released April 2025.3Press articlefunkykit.com/news/montech-introduces-century-ii-power-supplyRead 14 October 2026Available on April 15, 2025 at 9 AM Eastern Time. Cybenetics received the unit on Apr 29, 2025. Last checked 14 October 2026.
- Power
- 850W
- Efficiency
- 80 PLUS Gold
- Modular cables
- Fully modular
- ATX version
- ATX 3.1
54 of 66 fields known.
General
- Model numbers
- Century II 850W1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Model Name Century II 850W. The maker prints no part number.
- GTIN / EAN
- 47105627472631Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: EAN 4710562747263.
- Announced
- 15 April 20252Press releasemontechpc.com/news-century-iiRead 14 October 2026Launch article dated 2025-04-15. The unit is available from that day (see the Funkykit launch report).
- Predecessor
- Not available
- Successor
- Not available
- Launch price (US)
- $89.92Press releasemontechpc.com/news-century-iiRead 14 October 2026Article: Starting at just $89.9. Funkykit lists the 850W model at US$ 89.9, the lowest of the three launch models. US price, no sales tax.3Press articlefunkykit.com/news/montech-introduces-century-ii-power-supplyRead 14 October 2026Century II 850 W: US$ 89.9. The 1050 W is US$ 109.9 and the 1200 W is US$ 129.9.
- Launch price (EU)
- Not available
- Markets
- Not available
- Colours
- Metallic Silver1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Overview text: a sleek metallic silver finish. The maker names no other colour for this wattage.
- Form factor
- ATX1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Form Factor ATX (140).5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: Type ATX12V. The maker lists form factor ATX (140).
- PCIe CEM version
- PCIe 5.11Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Overview: ATX 3.1 and PCIe 5.1 platform support.
- Modular cables
- Fully modular1Maker product pagemontechpc.com/century-ii-850wRead 14 October 20265Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: Cable Design Fully Modular.
- Built by (OEM)
- Shenzhen Xinweiye Technology (XWY)5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: OEM/ODM Shenzhen Xinweiye Technology Co., Ltd. Tom's Hardware calls the company XWY.7Reviewtomshardware.com/pc-components/power-supplies/montech-century-ii-gold-850w-atx-3-1-power-supply-reviewRead 14 October 2026Internal Design: the OEM is Shenzhen Xinweiye Technology Co., typically referred to as XWY.
Power
- Rated continuous power
- 850W1Maker product pagemontechpc.com/century-ii-850wRead 14 October 20265Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Manufacturer-provided information: Rated Power 850 W.
- Full power rated up to
- 40°C1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Operating Temperature 0-40 C. Tom's Hardware prints the power table as Rated @ 40 C. The Cybenetics report leaves its continuous full load temperature row empty.7Reviewtomshardware.com/pc-components/power-supplies/montech-century-ii-gold-850w-atx-3-1-power-supply-reviewRead 14 October 2026Power specifications table titled Rated @ 40 C. Same figure as the maker's operating temperature.
- 12V rail design
- Single rail5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Power Specifications: one +12V column with 70.8A and 849.6W, and one OCP result for 12V.
- +12V max current
- 70.8A1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026DC Output table: +12V 70.8A, 849.6W.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026
- +12V max power
- 849.6W1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026DC Output table: +12V 70.8A, 849.6W.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026
- +3.3V and +5V combined power
- 100W1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026DC Output table prints +3.3V 20A 100W and +5V 20A 100W. The Cybenetics power table has one merged 100W cell for 3.3V and 5V, so 100W is the combined limit.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026
- +5V standby current
- 3A1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026DC Output table: +5VSB 3A, 15W.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026
- AC input voltage
- Lowest100Highest240V1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026AC Input 100-240 VAC, 50-60 Hz, 10 A max.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Manufacturer-provided information: 100-240 Vrms, 10 A, 50-60 Hz.
- Alternative low power mode (ALPM)
- Yes5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Temperature and Compliance Info: ALPM compatible, checked.
Certifications
- Cybenetics efficiency at 115V
- Cybenetics Platinum5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Report 25PS2813A, certification ID 252813, issued May 13, 2025. The database name is Montech Century II Gold 850 ATX3. The badge is ETA Platinum at 115V.
- Cybenetics efficiency at 230V
- Cybenetics Platinum5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026ETA Platinum at 230V.
- Cybenetics noise at 115V
- A-5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026LAMBDA A- at 115V.
- Cybenetics noise at 230V
- A-5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026LAMBDA A- at 230V.
Measured
- Average efficiency at 115V (measured)
- 89.8%5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Average over more than 1450 load combinations at 115V. Tested May 10, 2025, ambient 28-32 C. The report lists no sample serial.
- Average efficiency at 230V (measured)
- 91.84%5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Average over more than 1450 load combinations at 230V.
- Light-load efficiency at 115V (measured)
- 70.357%5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Efficiency at 2% load (more than 500 W unit) at 115V.
- Average power factor at 115V (measured)
- 0.9855Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Average over more than 1450 load combinations at 115V. At 230V it is 0.945.
- Average noise at 115V (measured)
- 26.89dB(A)5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Average over more than 1450 load combinations at 115V, ambient 28-32 C, Bruel and Kjaer 2270 G4 sound analyzer. The 230V average is 26.26 dBA.
- Noise at full load at 115V (measured)
- 42.1dB(A)5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Typical load tests at 115V, 100% load row: 42.1 dB(A) at 1698 rpm fan speed, ambient about 30 C.
- Standby power with no load at 115V (measured)
- 0.073W5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Standby power consumption at 115V with no load on +5VSB: 0.0730 W. At 230V it is 0.1474 W.
- Hold-up time (measured)
- 22.4ms5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Hold-Up Time and PWR_OK Signal: hold-up time 22.4 ms, AC loss to PWR_OK 14.3 ms, at maximum continuous load.
- 12V ripple at full load (measured)
- 28.25mV5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Non-accredited. 12V ripple at full load at 115V. At 230V it is 29.21 mV.
- 12V load regulation (measured)
- 0.39%5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Non-accredited. 12V load regulation at 115V. At 230V it is 0.27%.
Cables and connectors
- Cables
Connector Connectors Cables Length to first plug (mm) Wire gauge Rated power (W) ATX 24-pin (20+4) 1 1 590 18AWG Not available CPU 8-pin (EPS, 4+4) 2 2 700 18AWG Not available PCIe 8-pin (6+2) 4 2 600 18AWG Not available 12V-2x6 1 1 600 16AWG 600 SATA power 8 2 500 18AWG Not available 4-pin Molex 4 1 500 18AWG Not available Source1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Cables table: 1 motherboard cable with a 20+4 pin plug, 2 CPU cables with one 4+4 pin plug, 2 PCIe cables with two 6+2 pin plugs, 1 12V-2x6 cable, 2 SATA cables with 4 plugs and 1 Molex cable with 4 plugs. Lengths and gauge come from the Cybenetics report.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Cables and Connectors table: ATX 20+4 pin 590 mm 18AWG, 2 x 4+4 pin EPS 700 mm 18AWG, 2 x 6+2 pin PCIe cables 600 mm then 150 mm with 4 plugs in total 18AWG, 12+4 pin PCIe 600 mm (600W) 16-26AWG, 2 SATA cables of 500 mm plus 3 x 150 mm spacing with 8 plugs in total 18AWG, 1 Molex cable 500 mm plus 3 x 150 mm with 4 plugs 18AWG. The 16-26AWG range of the 12V-2x6 cable includes the thin sideband wires, so the stored gauge is the 16AWG power wire.- CPU (EPS) connectors
- 2
- PCIe 8-pin connectors
- 4
- 16-pin GPU connectors
- 1
- SATA power connectors
- 8
- 4-pin Molex connectors
- 4
- Cable style
- Flat1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Overview: Flat cables and fully modular design.7Reviewtomshardware.com/pc-components/power-supplies/montech-century-ii-gold-850w-atx-3-1-power-supply-reviewRead 14 October 2026The cable bundle is all-black and entirely flat-ribbon in construction.
Fan
- Fan size
- 135mm1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Fan Size 135 mm.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: 135mm Fluid Dynamic Bearing Fan.
- Fan bearing
- Fluid dynamic (FDB)1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Fan Bearing FDB.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: 135mm Fluid Dynamic Bearing Fan (HA13525M12SF-Z).
- Fan mode
- Semi-passive1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Overview: 135 mm FDB fan with Smart Zero Fan mode.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: Semi-Passive Operation checked (selectable).
- Fan mode switch
- Yes5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026DUT Information: Semi-Passive Operation marked selectable.7Reviewtomshardware.com/pc-components/power-supplies/montech-century-ii-gold-850w-atx-3-1-power-supply-reviewRead 14 October 2026External Appearance: a smaller secondary toggle on the rear lets the user disable the hybrid mode and run the fan continuously.
Protection and parts
- Protections
- Over-current (OCP), Over-voltage (OVP), Under-voltage (UVP), Over-power (OPP), Over-temperature (OTP), Short-circuit (SCP), No-load (NLO), Surge and inrush (SIP)1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: OPP / OVP / UVP / SCP / OCP / OTP.5Measurementcybenetics.com/evaluations/psus/2813Read 14 October 2026Protection Features (Manufacturer) lists OPP, +12V OCP, OTP, SCP, surge and inrush current protection. Protection tests tick UVP at 90 V and 80 V and NLO. The maker lists OVP, which the report does not test.
- All-Japanese capacitors
- Yes1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Overview: 100% Japanese capacitors. The launch article says 100% Japanese electrolytic capacitors.2Press releasemontechpc.com/news-century-iiRead 14 October 2026Article: 100% Japanese electrolytic capacitors.
- MTBF (claimed)
- Not available
Monitoring and lighting
- Software monitoring
- Not available
- Software
- Not available
- Built-in power display
- Not available
Dimensions and weight
Front and side, drawn to scale.
- Dimensions
- Width150Height86Depth140mm(5.9 × 3.4 × 5.5 in)1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Dimensions (LxWxH) 140 x 150 x 86 mm, so depth 140, width 150, height 86. Tom's Hardware says the unit is 160 mm long. The maker value is stored and retailers copy it.
- Weight
- Not available
In the box
- In the box
- AC power cable, Mounting screws, Velcro-style cable straps, Cable ties, User manual7Reviewtomshardware.com/pc-components/power-supplies/montech-century-ii-gold-850w-atx-3-1-power-supply-reviewRead 14 October 2026In the Box: AC power cable, mounting screws, reusable Velcro-style cable straps, cable ties and a small user manual. Review published 7 September 2026.
Links
- Product page
- www.montechpc.com/century-ii-850w1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026
- Spec sheet
- Not available
- Manual
- Not available
- EPREL registration number
- Not available
Warranty
- Manufacturer warranty (source market)
- 10years1Maker product pagemontechpc.com/century-ii-850wRead 14 October 2026Specifications tab: Warranty 10 Years. The page is the global maker page and names no market.
Compare with
Pick a power supply to see both side by side. Differences are marked yellow.
Sources
We read 8 sources for this power supply. The numbers match the markers in the sheet.
- Maker product pagemontechpc.com/century-ii-850w
- Press releasemontechpc.com/news-century-ii
- Measurementcybenetics.com/evaluations/psus/2813
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