Take care to pull the heatsink up straight off the tray, as there is a fan connector to the right of the CPU and you will need to take care not to bend it.

The connector is seen in blue in the first picture.

You will see the old thermal paste on both the CPU and the heatsink; we will remove the old paste before reassembling the tray.

This is also a great time to dust the tray if you have a can of compressed air. I was surprised just how much dust was present in my heatsink alone!