Apple mac pro 8x User Manual

Mac Pro (8x) Troubleshooting — General Information 141
LED 2 CPU B (Lower Processor) Error 
LED 3 CPU A (Upper Processor) Error
Normally off. These LEDs come on if an error occurs or if the BootROM is corrupted. They do not 
depend on the DIAG_LED button being pressed.
Related symptoms include no video or the computer is hung up. If the BootROM is corrupted, 
the optical drive tray should eject, prompting for the insertion of a recovery disc to restore the 
BootROM.
Troubleshooting: 
With the computer...

Mac Pro (8x) Troubleshooting — General Information 142
Try swapping CPU A and CPU B locations. If the CPU Error LED follows the CPU, replace that • 
CPU.
LED 6 GPU Present
Normally on when DIAG_LED button is pressed. 
If this LED is on, it indicates there is a graphics card installed and recognized by the computer. 
It does not indicate that the graphics card is fully functional. Some graphics cards require 
additional power to function, which is available from connectors on the logic board. For these...

Mac Pro (8x) Troubleshooting — General Information 143
Interface (EFI) operations and the operating system is now in control. 
Troubleshooting: 
Check that LED 7 Power On LED is on. • 
Check that LEDs 2, 3, 4, and 5 are off. • 
Try removing any added hardware. • 
Try removing any added DIMMs. • 
Memory Riser Card Diagnostic LEDs
Both of the memory riser cards include diagnostic LEDs for each DIMM. Each of the LEDs will 
light if it detects an issue with the corresponding installed DIMM. These LEDs will...

Mac Pro (8x) Troubleshooting — General Information 14 4
Replace the video card.• 
Ext_Power LED
Normally off, this LED lights up if the auxiliary power isn’t being supplied.
Troubleshooting: 
Make sure the card’s auxiliary booster power cable is connected (if there is one). • 
Check connections from the power supply to the logic board. • 
Try a different auxiliary power cable. • 
Try a different video card. • 
Replace the video card.• 
Power Supply Verification 
To power on, the computer’s logic board...

Mac Pro (8x) Troubleshooting — General Information 145
the Boot ROM, and SMC updates update the System Management Controller firmware. The SMC 
manages fans and other environmental parameters that are independent of the Boot ROM.
Firmware symptoms can be easily mistaken for hardware issues (e.g., overheating issues, fan 
noise issues, etc.). Always check both EFI and SMC firmware versions and update if necessary 
before replacing any hardware components in the Mac Pro (8x).
The following lists describe...

Mac Pro (8x) Troubleshooting — General Information 146
Processor Heatsink and Processor Visual Inspection Instructions
The Mac Pro (8x) uses a special coating on the processor heatsink and processor to manage the 
temperature in the computer. Before installing a new or existing heatsink or processor, always 
make a visual inspection of the part. Specifically, check the application of the silver-colored 
coating on the underside of the heatsink and the top of the processor. In addition, check the...

Mac Pro (8x) Troubleshooting — General Information 14 7
Unacceptable examples
The following are examples of unacceptable applications of the coating. Return new parts or 
replace existing parts that exhibit similar applications. 
Void IVoid IISplash
Void I: The silver-colored coating shows missing areas of within the normal coated area.
Void II: The silver-colored coating shows missing areas along the edge of the coated area.
Splash: The silver-colored coating extends beyond the normal coated area....

Mac Pro (8x) Troubleshooting — General Information 14 8
To remove the particles, use the suction pipette that comes with the replacement heatsink and 
processor. ( The pipette is also available through GSX as part of the Mac Pro Grease Kit, part 
number 076-1258.) Depress the bulb end of the pipette, place the other end over the particle, 
and release the bulb. The particle will be suctioned into the pipette. 
Once you have removed all stray particles, place the pipette inside the resealable bag included...

Mac Pro (8x) Troubleshooting — Symptom Charts 149
Symptom Charts
How to Use the Symptom Charts 
The Symptom Charts included in this chapter will help you diagnose specific symptoms related 
to the product. Because cures are listed on the charts in the order of most likely solution, try 
the cures in the order presented. Verify whether or not the product continues to exhibit the 
symptom. If the symptom persists, try the next cure. 
Note: If a cure instructs you to replace a module, reinstall the original...

Mac Pro (8x) Troubleshooting — Symptom Charts 150
Verify that processors’ mounting clamps are properly tightened. 8. 
Test whether the front panel board or power button is at fault. Remove the installed front 9. 
panel board and test with a known-good front panel board. 
Replace front panel board. 10.  
Replace power button. 11 . 
Replace power supply. 12.  
Replace logic board. 13 . 
Power-on LED illuminates when pressed in, but goes out when button is released, 
there is no boot tone or video, but you...