In the first picture, see the outside facing part of the chip that touches the heatsink. From the factory the top of the chip doesn't have any thermal compound on it. This is where I chose to add Arctic Silver thermal paste to help with the thermal protection of the chip. This is optional.

In the second picture you can see the defective mirror surface in the DLP chip. A good mirror surface should look clean with a rainbow effect. This defective mirror shows many small spots.

In the third picture you can see the socket that the DLP chip fits in to. When installing your replacement chip it simply pushes in.