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Edit Step 33  ¶ 

• While holding the plastic retainer down against the board, use the tip of a spudger to pry the PRAM battery out of its housing.
• Failure to hold the plastic retainer down during the prying process may result in it tearing off the motherboard.
• Before installing the heat sink onto the motherboard, it is essential to apply a new layer of thermal paste. This guide will show you how to do it.