Should I connect to the motherboard or power supply?

Connect to the motherboard header for speed control (best with 4-pin PWM). Connecting to PSU Molex runs it at full 12V speed, which is simpler but louder.

Why does the fan spin at 5V if the label says 12V?

Most motors have a wide tolerance range of 5V to 13V. However, they may not start below approximately 7V.

Do more blades mean better performance?

More blades increase static pressure (good for radiators) but may be louder. Fewer blades increase airflow (good for ventilation) with lower noise. 7-9 blades is a typical balance.

How do I know if the fan is dying?

Listen for clicking or grinding sounds. Check RPM via software; significantly low RPM is a red flag. Power off and flick the blade; wobble or stiffness indicates worn bearings.

404028mm Efficient Heat Dissipation Big Airflow Axial Flow Cooling DC Fan

Name: 40*40*28mm Efficient Heat Dissipation Big Airflow Axial Flow Cooling DC Fan
Brand: Fengxia Motor (Shanghai) Co., Ltd.
SKU: 2241772865

Shanghai, ChinaFengxia Motor (Shanghai) Co., Ltd.

40*40*28mm Efficient Heat Dissipation Big Airflow Axial Flow Cooling DC Fan

US$2.50-3.00

1 Piece

Sample price:US$2.50/piece.Request sample

Product profile

Customization

Available

Material

Aluminum Fan

Blade Material

PBT 94ulv

Model NO.

4028 DC Fan

Type

Axial Fan

Electric Current Type

Mounting

Free Standing

Certification

RoHS, ISO, CE

Transport Package

Paper Box

Specification

40*40*28mm

Origin

China

Production Capacity

100000 Pieces/Year

Key features

Wide Voltage Tolerance: Operates effectively within a 5V to 13V range for flexible power integration.

Multiple Bearing Options: Choose from Sleeve, Hydraulic, or Double-ball bearings for varied lifespan needs.

Full Customization Service: Offers customization from samples, designs, and full customization capabilities.

Multi-Industry Application: Suitable for drones, automotive, medical, and industrial control equipment.

Certified Quality Assurance: Products hold RoHS, ISO, CE, and FCC certifications for global compliance.

Durable Aluminum Construction: Features an aluminum fan body with PBT 94ulv blades for stability.

Flexible Pin Configuration: Supports 3-pin DC control and 4-pin PWM for precise speed management.

Professional Technical Support: Provides professional guidance and troubleshooting for installation and usage.

Company profile

Importers and ExportersHigh Repeat Buyers Choice

Fengxia Motor (Shanghai) Co., Ltd.

Shanghai, China

CertifiedBusiness Type: Manufacturer/Factory & Trading Company CertifiedR&D Capacity: ODM Service Available & OEM Service Available CertifiedCustomization Options: Customization from Samples, Customization from Designs, etc. CertifiedExport Year: 5 Years CertifiedNearest Port: Shanghai PortAverage Response Time: ≤3.19h

AI-Powered supplier vetting

SummaryThe supplier demonstrates strong customization, R&D, OEM/ODM, quality-control, and complaint-handling capabilities. It reports new products within the past year, provides customization from samples and designs through full customization, and serves known brands through OEM. Production includes two lines, inventory capability, defined inspection procedures, and four QA/QC inspectors. However, important operational limitations exist: no available SDK, no overseas agents, branches, warehouse, or showroom, no offline trade-show participation, and only one experienced export-trade employee. Manufacturing controls also show gaps, including no ongoing quantity reconciliation for each batch and no standard operating procedure for outsourced manufacturing. Financial evidence is represented only by years rather than substantive indicators, so credibility cannot be determined. The supplier holds an ISO9001:2015 certificate, but the available information does not establish broader certification coverage.

Supplier typeThe supplier operates as a manufacturer with two production lines, provides OEM and ODM services, offers inventory capability, and accepts FOB and EXW quotations. It also provides full customization, but lacks overseas agents, branches, warehouses, and showrooms.

CertificationsThe supplier reports an ISO9001:2015 certificate. No additional specific certifications are identified in the provided information.

After-Sales capabilityThe supplier has documented and followed procedures for customer complaints and corrective/preventive actions, supporting an established service-response process. However, it has no overseas agents, branches, warehouse, or showroom, which limits demonstrated overseas service infrastructure.

R&D capabilityThe supplier reports new products in the past year, provides ODM services, and assigns R&D personnel to product development, design drawings, production support, and specifications. Nevertheless, it has no available SDK and no design input, output, review, validation, or confirmation documents available for audit.

Production capacityProduction evidence includes two production lines, inventory capability, one-month average lead times in both peak and off-season periods, four QA/QC inspectors, written finished-product inspection instructions, and multiple listed production machines. Controls are weakened by the absence of ongoing batch quantity reconciliation and a standard operating procedure for outsourced manufacturing.

Customization capabilityThe supplier explicitly supports customization from samples, customization from designs, and full customization, with the same capability reported under both R&D and design services. This directly demonstrates broad customization coverage.

Product Q&A

Q:What causes fan noise and how to fix it?

Noise may result from loose screws, dust buildup, or bearing type. Fix by tightening mounts, cleaning dust, lowering RPM, or choosing hydraulic bearings for a balance of quietness and durability.

Q:Which direction should the fan face?

Follow the arrows on the frame: intake (cool air in) for front/side, exhaust (hot air out) for rear/top. Tower coolers should push air toward the rear exhaust.

Q:What is the difference between 3-pin and 4-pin fans?

3-pin uses DC voltage control for fixed or stepped speeds. 4-pin uses PWM for automatic, precise, and quieter speed variation controlled by the motherboard.

Q:How long will the fan last?

Lifespan depends on the bearing: Sleeve (~2-3 years), Hydraulic (~4-5 years), and Double-ball (5-10 years, tolerant of 24/7 use).

Q:How can I make the fan quieter?

Use rubber pegs instead of metal screws, use a low-noise adapter to drop voltage, or adjust the BIOS fan curve to keep RPM low until temperatures rise.