AXIOMTEK IMB760 User Manual page 29

Step 4 Place the CPU cooler module on the CPU socket on the motherboard, and
then align pin A to hole A and pin B to hole B simultaneously.
The installation direction of CPU on the clip and cooler module can affect
how the air flows through chassis, please follow the installing instructions
to ensure that the CPU is properly installed for best cooling performance.
Note
Board and Pin Assignments
Hole A
Hole B
IMB760 LGA4189 EATX Motherboard
Pin A
Pin B
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