BLOG

3U Server Heatsink 107-0033-1: High-Density Cooling Guide

Model 107-0033-1 is a skiving-fin server heat sink specified for both 1U and 3U platforms, using a 5000 RPM dual-ball-bearing fan to push air through a 51-fin stack in high-density enclosures. This guide covers its specifications, thermal behaviour, installation, maintenance and how it positions against other server cooling options.

Skiving Fin Technology Explained

Most entry-level heat sinks are extruded: aluminium is pushed through a die to form a profile with fins already attached. Extrusion is cheap, but it limits you to relatively thick fins and a coarse pitch, because the die has to withstand the forming pressure.

Skiving works differently. A cutting tool slices through a solid aluminium block, peeling up a fin and leaving it attached to the base as one continuous piece of metal. That gives three advantages:

  • Higher fin density. 51 fins in an 89 × 89 mm footprint, versus what an extrusion can achieve in the same area.
  • No bond-line resistance. Base and fins are the same piece of aluminium, so there is no solder or epoxy interface adding thermal resistance between them.
  • Better fin aspect ratio. Skived fins can be made taller and thinner, raising surface area without proportionally raising weight.

The trade-off is tooling cost and a base that is inherently a fixed geometry — which is why custom skived designs are usually an OEM project rather than a catalogue variation.

Technical Specifications of Model 107-0033-1

ParameterSpecification
Model3U heatsink 107-0033-1
Overall Dimension89 × 89 × 29 mm
Weight309 g
TDP95 W
Fin ConstructionSkiving
Fin Count51 fins
Base MaterialSKIVING aluminium
Surface TreatmentPassivation
Fan Dimension75 × 75 × 16 mm
Fan Blades21 blades / black
Rated Voltage / Current12 V DC / 0.52 A
Power Consumption6.24 W
Fan Speed5000 RPM ±10% (PWM)
Bearing TypeTwo ball bearing
Fan Life70,000 hours
Static Pressure36.29 mmH2O (MAX)
Air Flow10.57 CFM (MAX)
Noise50 dBA
Connector2.54-4Pin PWM
CPU CompatibilitySocket 115X / 1700
Package410 × 310 × 125 mm, 24 pcs, 8.7 kg net

Read the specification as a system rather than a list. The 36.29 mmH2O static pressure is the defining number: this fan is selected to overcome the obstruction inside a populated server chassis, not to maximise free-air CFM. The low air-flow figure (10.57 CFM) is the direct consequence — a 75 × 16 mm fan cannot deliver both high pressure and high free-air volume, and for a server the pressure term is the one that determines whether air actually reaches the fins.

The passivation surface treatment forms a thin protective oxide layer that inhibits corrosion without the dimensional change of plating. For an aluminium part that will live in a humid rack for years, that matters.

High-Density Cooling: Why It Matters

Three effects drive temperature in a high-density rack, and a heat sink only addresses one of them directly — which is why selection has to consider all three:

  1. Die-level heat flux. Modern processors concentrate 95 W into a small area. The heat sink's job is to spread that flux across enough surface that air can carry it away. Skiving helps here through the continuous metal path.
  2. Internal chassis recirculation. Air that has already passed over one component arrives at the next one warmer. High static pressure helps push through this rather than stalling.
  3. Facility inlet temperature. No heat sink can cool below the temperature of the air it receives. Every degree of hot-aisle recirculation is a degree added to the CPU.

Installation Guide: Step-by-Step

  1. Confirm the platform. This part is specified for 1U/3U server platforms with socket 115X or 1700. Verify before disassembly.
  2. Power down and ground yourself. Observe standard ESD precautions.
  3. Remove old TIM completely. Use isopropyl alcohol and a lint-free wipe until the IHS and heat sink base are uniformly clean.
  4. Apply fresh TIM. A central dot sized to roughly a grain of rice. Passivated aluminium is slightly more sensitive to excess paste than a copper base — keep the layer thin.
  5. Seat vertically and fasten diagonally. Alternate opposite corners to load the base evenly.
  6. Connect the 4-pin PWM header to CPU_FAN. Configure the fan curve so idle duty sits around 30–40% — at 5000 RPM this fan is loud at 100%, and there is no reason to run it there at idle.
  7. Baseline the temperatures. Record idle and sustained-load values. Without a baseline, a future gradual rise is invisible.

Maintenance Schedule

IntervalActionWhy
MonthlyCheck BMC/BIOS for fan RPM anomaliesDetects bearing wear before it becomes a thermal event
Quarterly (dusty)Clean fins with low-pressure air along the channelsTight fin pitch traps dust that acts as an insulator
Semi-annual (filtered DC)Full clean and temperature baseline comparisonConfirms the cooling system still performs to specification
AnnuallyInspect retention hardware and TIM conditionThermal paste degrades; mounting pressure can relax over thermal cycles
AnnuallyReview fan life against the 70,000-hour ratingPlan replacement before failure rather than after

Common Issues & Troubleshooting

SymptomLikely CauseCorrective Action
Fan reports 0 RPMBearing seizure or disconnected headerCheck the connector first, then replace the fan
Progressive temperature increaseDust in the 51-fin stackClean along fin channels; re-baseline afterwards
Noisy at idleFan curve running the 5000 RPM fan at full dutySet a PWM floor of 30–40% in BIOS or BMC
Throttling at high ambient onlyFacility inlet temperature above designAddress rack airflow; the heat sink is not the limiting factor
Uneven fin temperaturesAirflow misaligned with fin channelsRotate the heat sink or adjust ducting to match the airflow axis
Retention hardware looseningThermal cycling over long serviceRe-torque diagonally to specification; inspect for deformation

Comparison with Other Server Cooling Solutions

Model / ApproachTDPFanPressureNotes
107-0033-1 skiving fin95 W75 mm, 5000 RPM36.29 mmH2OHighest pressure; best for obstructed 1U/3U paths
103-0011-1 skiving fin95 W75 mm, 5000 RPM36.29 mmH2OSame thermal core, 1U-optimised variant
104-0046-1 copper heat pipe125 W60 mm, 7000 RPM16.05 mmH2OHigher TDP, larger heat-spreading capability
Passive extrusion35–65 WNone—Silent; depends entirely on chassis airflow

Selection Checklist

  • Vertical clearance verified at 29 mm plus socket and retention stack-up.
  • TDP at or below 95 W.
  • Socket confirmed (115X / 1700).
  • Chassis airflow axis aligned with the fin channels.
  • PWM fan curve configured — do not run a 5000 RPM fan at fixed full duty.
  • Dust interval defined for the deployment environment and logged.

OEM / ODM Customization

Skived heat sinks are inherently custom-friendly on the tooling side once the die is made, which makes them a good fit for OEM programmes with a fixed chassis. We can adapt fin count and pitch, base footprint, mounting pattern and fan selection, and we run the full cycle from requirement analysis through sample testing to mass production.

Send us your mechanical drawing and target TDP to start a custom evaluation.

ATX Cooler 104-0020-1: Performance, Overclocking & Buying Guide
2U Server Heatsink 104-0046-1: Specifications, Installation & Maintenance