HP zx6000 Processor Upgrade Instructions page 11

4. Use the four locator posts on the heatsink and the turbo fan
power cable to properly align the fan and processor assembly
on the system board. The four locator posts will fit in locator
holes on the system board processor mount. The turbo fan
power cable must be positioned so that it is located on the
side of the heatsink that faces the front of the system.
Aligning the Turbo Fan and Processor Assembly
1
Locator posts
2
Locator holes