Apple mac pro User Manual

							Mac Pro Take Apart — Processor Heatsinks 71
Replacement Note: Before reinstalling an existing processor heatsink, follow these directions for 
applying new thermal grease to the underside of the heatsink. 
Using the alcohol pad included with the logic board or processor replacement part, clean off • 
any used thermal grease from the processor and the bottom of the heatsink.
Using the thermal grease included with the logic board or processor replacement part, apply • 
one dot of fresh grease to the raised square area on the bottom of the heatsink.
Spread the grease evenly across the square to a thickness of approximately 1 mm. • 
Warning: Do not apply more grease than recommended. The grease must not overflow the 
heatsink and come in contact with the processor connector.
Carefully align the posts on the heatsink with the mounting holes in the logic board, and • 
lower the heatsink straight down onto the processor.
To ensure the grease spreads evenly over the processor, lightly tighten the heatsink • 
mounting screws in the order indicated below. 
To affix the heatsink to the processor, again tighten the screws in the order indicated.•  
						

							Mac Pro Take Apart — Processor Heatsinks 72
Note: If you are replacing a processor heatsink with a new heatsink, do not reapply thermal 
grease. The new heatsink comes with thermal grease already in place, covered by a cap over the 
bottom of the heatsink. Before installing the heatsink, remove the cap.
Replacement Note: If you are replacing either the upper or lower processor heatsink with a new 
heatsink, apply the enclosed gasket to the top of the heatsink, as illustrated below.
Replacement Note: If you are replacing the lower processor (CPU B) heatsink with a new 
heatsink, install the enclosed bumpers on either side of the heatsink, as illustrated below. Do not 
add bumpers to the heatsink for the upper processor (CPU A). 
						

							Mac Pro Take Apart — Memory Cage with Rear Fan 73
Memory Cage with Rear Fan
The rear fan is part of the memory cage assembly. If you need to replace the rear fan, you must 
replace the entire memory cage assembly.
Note: Every time you remove the memory cage, you must replace the thermal grease on 
the processor heatsinks. New grease and alcohol wipes for removing the previous grease are 
available as a separate kit (part number 076-1225). Instructions for applying the grease are 
included with the processor heatsinks procedure.
Tools
The only tools required for this procedure are pliers, wirecutters, and a socket wrench.
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
Top and bottom memory card• s
Processor heatsink cove• r
Front fan assembl• y
Processor heatsink• s 
						

							Mac Pro Take Apart — Memory Cage with Rear Fan 74
Part Location
Procedure
Disconnect the rear fan cable from the logic board.1. 
Lift the memory cage out of the enclosure.2.  
Replacement Note: When installing the memory cage, make sure all cables are out of the way so 
that the cage sits properly and the cable harness below it is not pinched or damaged when you 
tighten the screws. 
						

							Mac Pro Take Apart — Memory Cage with Rear Fan 75
Replacement Note for Cages with Stripped Screws: If either of the two short mounting 
screws for the memory cage stripped while you were attempting to take out the heatsink cover 
(see step 2 in “Processor Heatsink Cover,” the screw and hex standoff will stay attached to 
the memory cage when you remove it. In this case, before replacing the memory cage in the 
enclosure, do the following.
•  Using pliers and a socket wrench, separate the hex standoff from the mounting screw.
•  Replace the hex standoff in the enclosure.
Note: To avoid future problems, make sure both standoffs are securely fastened before you 
reinstall the memory cage.
Note: Order screw 922-7703 to replace any stripped, short screws used in securing the memory 
cage.. 
						

							Mac Pro Take Apart — Processors 76
Processors
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.
Note: Every time you remove a processor, you must replace the thermal grease on the processor 
heatsink. New grease and alcohol wipes for removing the previous grease are included with 
replacement processors. Instructions for applying the grease are included with the processor 
heatsinks procedure.
Identifying Version 1 and Version 2 Processors
There are two versions of the processor, Version 1 and Version 2, which must be replaced like-for-
like. In addition, both processors in a dual configuration must be the same version, either 
Version 1 or Version 2. Different versions in the same computer could cause a system failure.
Note: You may still replace a single processor, but you must replace it like for like. There is no 
performance advantage to either version of the processor.
To identify the correct processor for the computer you are repairing, please check its 
configuration code (the last three alphanumeric characters in the serial number for the 
computer). The following table lists the configuration codes that use Version 2 processors; all 
other configuration codes use Version 1 processors. If you do not have the correct processor, 
please order it from GSX.
Configuration CodeVersion 2 Processor
0KW, 0L0, 0L5, 0L7, 0LD, 0LE, 0LH, 0GP2.0 GHz  (661-4612)
0KT, 0GN, 0KY, 0KZ, 0L1, 0L2, 0L4, 0L6, 0L9, 0LA, 0LC, 0GP2.66 GHz  (661-4613)
0KV, 0KU, 0HA, 0KX, 0L3, 0L8, 0LB, 0LL, 0LM, 0LP, 0GP3.0 GHz  (661-4614)
Tools
No tools are required for this procedure. However, you may find a flat-blade screwdriver helpful in 
releasing the processor holder latch. 
						

							Mac Pro Take Apart — Processors 77
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
Top and bottom memory card• s
Processor heatsink cove• r
Front fan assembl• y
Processor heatsink• s
Memory cag• e
Part Location 
						

							Mac Pro Take Apart — Processors 78
Procedure
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.   
						

							Mac Pro Take Apart — Processors 79
Lift the processor out of the holder.3. 
Important: When removing or installing a processor, always hold the processor by the edges. 
Be extremely careful not to touch the gold pins on the bottom of the processor, as this type of 
connector is very sensitive to contamination. Also be careful not to touch the gold pins in the 
processor socket on the logic board. 
						

							Mac Pro Take Apart — Processors 80
Note: You can identify the processor by the speed etched on the processor can, as illustrated 
below. You must clean off the thermal grease from installed processors to see the speed.
Replacement Note: Before installing a replacement processor, remove the protective cap 
covering the new processor’s connector.