Your data center may not be built for today’s thermal demands. With all the attention that’s paid to cooling and ventilation, you’d be hard-pressed to believe that’s true. But it is, a nd here’s why. For a long time, data centers were designed around racks that operated in the 3–8kW range. Even large data centers were built to accommodate only about 10–15kW racks in higher-density deployments. However, with today’s AI clusters and GPU-heavy infrastructures, data centers are rapidly pushing rack densities toward 30–50kW. Some are even approaching 100kW.
Those demands are magnitudes beyond what many data centers were built to accommodate. Their computer room air conditioning (CRAC) can’t provide a cool environment under those conditions. They become increasingly inefficient and eventually become totally incapable of maintaining stable operating conditions. As expected, all of that extra thermal creation takes a toll on your hardware, hurting performance and shortening lifespans.
The Modern Requirements for AI Data Centers
With great computing power comes great cooling needs. That’s just the way it works; every watt consumed becomes heat. With advancements in AI computing, a new approach to data center thermal management also emerges.
The New Data Center Cooling Standards
- Hot/cold aisle containment
- Rear door heat exchangers (RDHx)
- Direct-to-chip liquid cooling
- In-row cooling
- Hybrid thermal architectures
While the methods of cooling data centers have changed significantly, the core principle remains the same. Cooling must be a core infrastructure strategy when designing and updating data centers. It is a pivotal component of overall facility performance.
Why Traditional CRAC Units Aren’t Enough
The cooling strategy of traditional CRAC systems was simple but effective for the era. The CRAC flooded a room with cold air. The servers drew in cool air on their front side and exhausted warm air out the back. The warm air that has been evacuated rises in the room, where the CRAC cools it again.
Basically, the room became a giant mixing chamber, blending cool and warm air. However, that approach isn’t effective for 30–50kW data centers.
Why HVAC CRAC Can’t Cool Modern Data Centers
- Heat output is highly concentrated
- Airflow limitations
- Hot air builds faster than room-level CRAC systems can remove it
- Racks can ingest warm air instead of cooled air
- Server inlet temperatures rise dangerously
Dangers of Hot Data Centers
- Reduced hardware lifespan
- Thermal throttling
- Unexpected shutdowns
- Higher power usage effectiveness (PUE)
Best Techniques for Data Center Cooling
Hot Aisle/Cold Aisle Containment
One of the first improvements to data center cooling is airflow containment. In traditional CRAC environments, hot and cold air are mixed. That’s not a great solution. Now data centers use a containment strategy that separates the two airflow streams.
Cold Aisle Containment
Cold air is enclosed and delivered directly to the server intakes. That creates more predictable temperatures, improving cooling efficiency. It also eliminates air mixing, making CRAC systems more effective.
Hot Aisle Containment
Hot air is also contained and removed from the space. That is a go-to for high-density environments. Hot-aisle containment enables easier heat extraction and improved efficiency at scale. Containment (cold and hot) can significantly improve cooling performance without requiring other, more costly, infrastructure upgrades.
Rear Door Heat Exchangers (RHDx)
As rack density increases, containment alone may not be enough. RHDx places liquid-cooled heat exchangers directly on the rear of each rack. This means the heat is immediately cooled as it exits the server, greatly reducing the room’s heat load.
Direct-to-Chip Cooling
The best solution for data centers with extreme AI densities (50kW to 100kW+ racks). Cold plates are attached directly to CPUs, GPUs, and high-power accelerators. Liquid circulates through the plates to remove heat directly from the silicon. This approach is vastly more efficient than approaches based on moving air. It also produces the most consistent chip temperatures, reducing thermal throttling.
Strategizing Data Center Cooling
Less than a decade ago, compute availability was the primary constraint on data center scaling. Today, dat centers face new factors, including cooling capacity, water availability, electrical infrastructure, floor loading, pipe routing, and placement of coolant distribution units (CDUs).
Essentially, data center design has transitioned from challenging to complex, with the biggest challenges coming from cooling rather than computational.
Key Questions Regarding Data Center Cooling
- What is our current rack density?
- What densities are expected within five years?
- Can existing cooling scale economically?
- Is containment optimized?
- Are we prepared for liquid cooling infrastructure?
The First Step is Often Hybrid Cooling
Liquid cooling is a more effective option for data center cooling, but it also comes with a high cost. That is why many data centers, especially those scaling up, turn to a hybrid solution that blends CRAC units, containment strategies, RHDx, and targeted liquid-cooled AI rows. The hybrid approach meets cooling needs and allows for phased-in capital expenditures.
The Future of High-Density Cooling
Innovation is happening rapidly as the demand for data centers grows and resistance to public and government regulations increases.
One of the major areas of advancement is warm-water cooling. Consider this a super high-efficiency liquid system that greatly lessens environmental impacts. Another option is immersion cooling. Radical sounding but effective in use, servers are submerged in dialectic fluids. AI is also being used to solve the challenge. AI-driven thermal optimization enables dynamic cooling management through telemetry and automation. Another interesting idea is modular high-density pods. Those are purpose-built AI infrastructure zones that optimize cooling.
All of these innovations and more are needed as the era of low-density server rooms begins to sunset. Organizations and data centers planning for AI growth must consider cooling as a strategic infrastructure layer.
Ready to Future-Proof Your Data Center Cooling for AI Infrastructure?
Ensuring your data centers can handle the massive thermal load of AI is a big part of future-proofing ongoing operations. Identifying and deploying the best approach to achieve it requires working with an expert. Matrix-NDI solves the challenges of your business operations by unlocking the full ROI of your technology investments. We design and install networks built for maximum speed and perfectly matched to bandwidth demands.
Why Work With Matrix-NDI?
We have on-staff Registered Communications Distribution Designers (RCDD), coast-to-coast service, and elite data networking partners, including Extreme Networks, Nile, and others. Ultimately, Matrix-NDI aligns your business with the devices, internet service, and software to achieve all technical objectives. We invite you to reach out with your needs and see how our expertise, partnerships, and national scale can be leveraged to solve them.
Contact Matrix-NDI to get started. Let’s build smarter, safer, more connected spaces — together.
