High efficiency cooling for compute systems

A compute tray comprising:

• a substrate;
• a plurality of computing resources on the substrate;
• a heat sink assembly on the substrate, wherein the heat sink assembly comprises fin banks arranged in a T-shape.

A method of cooling a compute system, the method comprising:

• directing air across a T-shaped heat sink bank within a compute tray of a plurality of compute trays to cool compute resources within the compute tray;
• and
• upon determining one or more switch trays are operating to connect compute resources within the plurality of compute trays, increasing air flow through the one or more switch trays using an external fan bank comprising a plurality of fans directing air through a plenum positioned at a rear of the one or more switch trays.