How Do I Size A Dry Cooler for GPU Servers?

To size a dry cooler for GPU servers, follow these core steps:

1. Determine heat load
   Total IT load (kW) × ~1.05–1.10 (losses).
   Example: 500 kW IT → ~525–550 kW heat rejection.

2. Define water temperatures
   Typical GPU liquid cooling:

• Supply: 30–35 °C

• Return: 40–45 °C

3. Define ambient design temperature
   Use worst-case outdoor dry-bulb (e.g. 35 °C).

4. Calculate approach temperature
   Approach = Leaving water temp − Ambient air
   Common: 5–8 K (smaller = larger cooler).

5. Select dry cooler capacity
   Choose a unit rated ≥ required kW at:

• Design ambient

• Specified water temps

• Acceptable fan power and noise

6. Check redundancy & scalability
   Apply N+1 or modular design for uptime and future GPU expansion.

Key sizing tips

• Higher water temps = smaller, more efficient dry cooler

• EC fans enable better part-load efficiency

• Ensure compatibility with CDU and facility water chemistry