Direct-to-Chip Cooling

Overview

Direct-to-Chip (DTC) Cooling, also called Direct Liquid Cooling (DLC), uses cold plates mounted directly on processor dies to transfer heat to a circulating liquid coolant (typically propylene glycol solutions such as PG25 or bio-based alternatives). The coolant flows through a closed-loop TCS (Thermal Cooling System) to CDUs (Coolant Distribution Units) where heat is rejected to facility water or dry coolers. DTC is the dominant liquid cooling modality for current-generation AI data centers, preferred over immersion cooling for its lower complexity, easier serviceability, and compatibility with existing rack infrastructure.

The OCP Cooling Environments project has focused significant standardization effort on DTC through the Coldplate Base Specification (16 mandatory tests across 5 categories), PBMC connectors (36 LPM blind-mate couplings), and CDU specifications (Project Deschutes). The primary growth driver is NVIDIA GPU TDP scaling from approximately 2,400W current generation toward ~7,000W by 2029, making liquid cooling mandatory rather than optional. Liquid cooling shipments grew 484% during 2024, driven predominantly by DTC cold plate demand for Blackwell/GB200 GPU platforms. As GPU thermal design power continues to rise, cold plate designs are becoming more sophisticated, with two-phase dielectric DTC systems emerging as a next-generation option and L2L (Liquid-to-Liquid) CDU architecture projected to constitute 80% of installed gigawatt-scale DLC capacity by 2026.