Apple mac pro 8x User Manual

Mac Pro (8x) Take Apart — Processor Heatsinks 71
Using a long-handled, magnetized 3 mm flathead hex screwdriver, loosen the four captive 2. 
mounting screws for the upper processor heatsink in the order indicated below. 
Lift the heatsink straight up and out of the enclosure.3. 
Disconnect the cable connector for the lower processor (CPU B) heatsink. 4.  

Mac Pro (8x) Take Apart — Processor Heatsinks 72
Using a long-handled, magnetized 3 mm flathead hex screwdriver, loosen the four captive 5. 
mounting screws for the lower processor heatsink in the order indicated below. 
6. Carefully tilt the heatsink so that it clears the bottom lip of the enclosure and then lift the 
heatsink out of the computer.
IMPORTANT:
Remember that you 
cannot leave the 
heatsink separated 
from either the upper 
or lower processor for 
more than 30 minutes. 

Mac Pro (8x) Take Apart — Processor Heatsinks 73
Visual Inspection of Heatsink Gasket
Before installing a new or existing heatsink, check that the gasket that surrounds the silver-
colored coating on the underside of the heatsink is in good condition, as illustrated below.
Replace the gasket if it shows obvious damage, such as cracks, folds, and broken-off surfaces, or 
if it is dislocated from the heatsink. The gasket is available through GSX as part of the Mac Pro 
Grease Kit, part number 076-1258....

Mac Pro (8x) Take Apart — Processor Heatsinks 74
Using the pre-measured syringe of Krytox grease from the kit, evenly apply a bead of grease • 
around the full perimeter of the heatsink gasket. Apply the full syringe of grease to the 
gasket. 
Warning: Do not apply more grease than recommended. The grease must not overflow the 
heatsink and come in contact with the processor connector.
Do not apply any grease to the processor.• 
Installing New Processors
Do not apply new grease to either the heatsink or...

Mac Pro (8x) Take Apart — Processor Heatsinks 75
Replacement Instructions for Heatsink
Note: If you are re-installing an existing heatsink, go directly to step 1 below. If you are installing 
a replacement heatsink, first do the following:
Unpack the new heatsink according to the instructions included in the parts box.• 
• Remove the protective cap covering the underside of the heatsink and transfer it to the 
heatsink you are returning to Apple. 
Apply the top gasket included in the parts box to the top...

Mac Pro (8x) Take Apart — Processor Heatsinks 76
If you are replacing the lower processor heatsink with a new heatsink, install the bumper • 
included in the parts box on the side of the heatsink.
Visually inspect the gasket on the underside of the heatsink. See “1. Visual Inspection of 
Heatsink Gasket” earlier in this procedure. 
Carefully align the posts on the lower heatsink with the mounting holes in the logic board, 2.  
and lower the heatsink onto the processor.
Lightly tighten the heatsink...

Mac Pro (8x) Take Apart — Processor Heatsinks 77
Disposal Instructions
Place all disposable materials used in removing or replacing a processor heatsink or processor 
inside the resealable plastic bag included with the replacement module. (Disposable materials 
include such items as protective gloves, alcohol wipes, lint-free cleaning cloths, Krytox grease and 
syringe, suction pipette, and heatsink gasket.) Pack this bag along with the failed module in the 
box that the replacement module came in, and...

Mac Pro (8x) Take Apart — Processors 78
Processors
The Mac Pro (8x) computer uses a special coating on the processor heatsink and processor to 
manage the temperature in the computer. The silver-colored coating comes applied to the 
underside of the heatsink and the top of the processor.
Use the following guidelines when handling the processor heatsink and/or processor:
• Wear disposable nitrile or latex gloves.
Avoid touching the silver-colored coating on the underside of the heatsink and the top of •...

Mac Pro (8x) Take Apart — Processors 79
Tools
No tools are required for this procedure. However, you may find a flat-blade screwdriver helpful in 
releasing the processor holder latch.
Preliminary Steps
Before you begin, open the computer, lay it on its side with the access side facing up, and remove 
the following:
Hard drives and hard drive carriers in drive bays 1 and • 2
PCI Express card installed in slot • 1
Any 12-inch PCI Express card• s
Processor heatsink cove• r
Front fan assembl• y
Top and...

Mac Pro (8x) Take Apart — Processors 80
Procedure
Note: This procedure illustrates how to remove the lower processor (CPU B). The instructions are 
the same for removing the upper processor (CPU A). You may, however, want to use a flat-blade 
screwdriver to release the latch on the upper processor.
Release the latch on the metal processor holder. 1. 
Note: You may want to use a flat-blade screwdriver to release the latch on the upper 
processor. 
Rotate the top of the holder to the open position. 2.