Cold Plates for AI Server and Data Center Liquid Cooling
Cold plates are the primary heat transfer interface in direct-to-chip liquid cooling systems. They mount directly on the processor, GPU, or power electronics package and transfer heat from the component surface into the flowing coolant. Cold plate design — including internal channel geometry, base material, and port configuration — directly determines thermal performance and pressure drop.
How It Works
A cold plate consists of a thermally conductive base that contacts the heat source and an internal channel structure through which coolant flows. Heat conducts from the component through the base material into the channel walls, where it transfers into the coolant by convection. The internal geometry — micro-channel, pin-fin, or serpentine — is optimized to maximize heat transfer area while managing pressure drop. Coolant enters through an inlet port, flows through the internal channels, and exits through an outlet port to the manifold or CDU return circuit.
Applications
- GPU direct-to-chip cooling in AI training and inference servers
- CPU liquid cooling in high-density compute nodes
- AI accelerator (ASIC) thermal management
- Power electronics cooling in CDU and power supply units
- HPC processor cooling
- OEM liquid-cooled server and storage equipment
- Edge AI compute thermal management
- Custom liquid-cooled electronics assemblies
Key Technical Specifications
| Base Materials | Copper, aluminum 6061, stainless steel 316L |
| Internal Structure | Micro-channel, pin-fin, serpentine, parallel channel |
| Thermal Resistance | Application-specific — specify heat load and flow rate |
| Pressure Drop | Optimized per flow rate requirement — specify target |
| Port Configuration | G1/4", barb, push-fit, QDC; custom port locations |
| Surface Finish | Lapped, anodized, electroless nickel-plated options |
| Mounting | Screw-down, spring-loaded, custom bracket |
| Footprint | Custom to processor or component package dimensions |
| Thermal Interface | Bare copper/aluminum, indium foil, TIM pad options |
| Fluid Compatibility | Water, glycol/water, dielectric fluids |
| Certifications | Options available depending on configuration and manufacturing partner. Please specify project requirements. |
Specifications are indicative. Final parameters depend on manufacturing partner and project configuration. Contact us with your specific requirements.
Available Configurations
- Copper micro-channel cold plate — highest thermal performance for GPU and CPU cooling
- Aluminum cold plate — lower cost, lighter weight for less demanding applications
- Stainless steel cold plate — corrosion resistance for aggressive coolant chemistries
- Single-pass serpentine channel — simple, low pressure drop
- Multi-pass parallel channel — higher heat transfer, higher pressure drop
- Pin-fin structure — high surface area for maximum heat transfer
- Integrated QDC ports for tool-free server maintenance
- Custom footprint to match specific processor or ASIC package
Materials
Operating Conditions
- Heat load: specify processor TDP and expected operating power
- Coolant inlet temperature: typically 20°C–45°C for data center applications
- Flow rate: specify target flow rate per cold plate
- Pressure drop: specify maximum allowable pressure drop
- Coolant chemistry: confirm glycol concentration and inhibitor package
- Mounting force: specify if spring-loaded or screw-down mounting is required
- Vibration: specify if equipment is subject to transport or operational vibration
Selection Guide
Cold plate selection requires: (1) Thermal performance — specify the processor TDP, coolant inlet temperature, and maximum allowable junction temperature to determine required thermal resistance; (2) Pressure drop — the cold plate pressure drop must be compatible with the pump and system design; (3) Base material — copper offers the highest thermal conductivity; aluminum is lighter and lower cost; stainless steel for corrosive environments; (4) Footprint — the cold plate base must match the processor package dimensions and mounting hole pattern; (5) Port configuration — match to the manifold or hose connection type; (6) Surface finish — electroless nickel plating protects copper from corrosion in glycol/water systems.
OEM & Custom Manufacturing
Custom cold plate designs are available for OEM server and AI accelerator manufacturers. Custom options include non-standard footprints for proprietary processor packages, integrated QDC ports, specific thermal performance targets, custom mounting configurations, and private label manufacturing. Provide your processor package drawing, TDP, and thermal budget for a design review.
Submit Custom RequirementQuality & Testing
Cold plates for AI server applications require pressure testing, leak testing, and thermal performance validation. Pressure testing to 1.5× working pressure is standard. Thermal resistance testing using calibrated heat sources is available for performance-critical applications. Cleanliness specifications — including particle count and flush requirements — should be stated to protect downstream components.
Frequently Asked Questions
What is the thermal resistance of a typical GPU cold plate?
Thermal resistance depends on cold plate design, base material, internal channel geometry, flow rate, and coolant properties. For high-performance copper micro-channel cold plates at typical data center flow rates, thermal resistance values of 0.05–0.15 °C/W are achievable. Specify your heat load, flow rate, and temperature budget for a design-specific assessment.
Can cold plates be used with dielectric fluids?
Yes, but material compatibility must be verified. Copper and stainless steel cold plates are generally compatible with engineered dielectric fluids. Aluminum may be susceptible to corrosion with some dielectric fluid formulations. Specify the fluid type and chemistry when requesting a quotation.
How is a cold plate mounted to a GPU or CPU?
Cold plates are typically mounted using the processor socket mounting holes with a spring-loaded retention mechanism to maintain consistent contact force across the thermal interface. The mounting force must be within the processor manufacturer's specified range to avoid package damage. Custom mounting brackets are available for non-standard configurations.
What thermal interface material is used between the cold plate and processor?
Common options include phase change thermal interface materials (TIM), indium foil, and liquid metal. The choice depends on the processor package, required thermal resistance, and serviceability requirements. Phase change TIM is the most common choice for maintainable server applications.
Need Cold Plates for Your Project?
Send your connection size, coolant type, flow requirements and estimated quantity. Our team will review the application and identify suitable manufacturing options.