Apple power mac g4 gigabit ethernet User Manual
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 3 Note: This entire procedure resets the computerÕs PRAM. Be sure to reset the computerÕs time, date, and other system parameter settings before returning the computer to the customer. Logic Board LEDs: Power Mac G4 (all models except PCI Graphics) There is one red LED on the Power Mac G4 (AGP Graphics/Gigabit Ethernet/Digital Audio/QuickSilver/QuickSilver 2002) logic boards. It indicates that there is power to the board and does not...
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 4 Power Macintosh G4 (PCI Graphics) Processor Module The logic board comes with a removable processor module. The processor should rarely fail and should be replaced only as a last resort. Processor modules can be ordered from Service. Note that when you replace the logic board on a Power Macintosh G4 (PCI Graphics), you must also change the processor jumper block and warranty sticker to be compatible with the processor module. Failure...
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 5 Resetting the Cuda Chip: Power Macintosh G4 (PCI Graphics) The Cuda is a microcontroller chip on the Power Macintosh G4 (PCI Graphics) logic board. Its function is to ¥ Turn system power on and off. ¥ Manage system resets from various commands. ¥ Maintain parameter RAM (PRAM). ¥ Manage the real-time clock. Many system problems can be resolved by resetting the Cuda chip (see the Symptom Charts for examples). Press the Cuda reset button...
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 6 Resetting the PCI Logic Board Resetting the logic board can resolve many system problems (see the Symptom/Cure tables for examples). Whenever you have a Power Macintosh G4 (PCI Graphics) computer that fails to power up, you should follow this procedure before replacing any modules. 1. Unplug the computer. 2. Press the Power On button on the front of the unit. 3 . Open the side access panel. 4. Remove the battery from the logic board....
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 7 Note: This procedure resets the computerÕs PRAM. Be sure to check the computerÕs time/date and other system parameter settings afterwards. Logic Board LEDs: Power Macintosh G4 (PCI Graphics) There are seven diagnostic LEDs on the Power Mac G4 (PCI Graphics) logic board. A graphic follows showing their location. DS1 = ATA drive activity If a CD and/or Zip are attached to the ATA bus, this LED will illuminate at power/on restart...
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 8 DS4 and DS5 = USB power for downstream devices DS5 = USB port 1- lower DS4 = USB port 2- upper (There is no DS2 or DS3 on the board.) When illuminated, these LEDs indicate that the computer is providing power (+5 V) to downstream USB ports. USB devices do not need to be connected in order for these LEDs to illuminate. However, if one or both of the LEDs is not illuminated and a USB device is/was attached (and the system has completed...
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TroubleshootingGeneral/Logic Board Troubleshooting - 1 9 other port can still be functional. These LEDs are not immediately illuminated at the beginning of a restart or cold power-on. During a successful/normal boot, the sequence will look like: 1. Unit is powered on and other LEDs will illuminate while DS4 and DS5 are off. 2 . Then DS4 and DS5 on for a second or two 3. Then off very briefly (1 second) 4. Then back on (confirms secondary PCI bus is initialized and power now available) These...
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TroubleshootingGeneral/Logic Board Troubleshooting - 2 0 DS6 = Ultra ATA bus activity DS6 indicates Ultra ATA bus activity. DS7 & DS8 = Power Indication In a working unit, these LEDs should be in sync with each other: both on or both off. If one LED is on and the other is off, there is a problem. DS9 = CPU Bus Request When illuminated, this LED indicates that the CPU is requesting the bus. This LED will rarely glow as brightly as the others (like the Ultra ATA LED) given that the CPU is...
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TroubleshootingGeneral/Logic Board Troubleshooting - 2 1 Power Macintosh G4 (PCI Graphics) LEDs Locator DS5 DS9 DS8 DS7 DS6 DS1DS4
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TroubleshootingGeneral/Power Supply Verification - 2 2 Power Supply VeriÞcation To start up, the Power Mac G4 logic board requires a ÒtrickleÓ power of +5V for AGP and PCI models, +28V for Gigabit Ethernet/ Digital Audio models, or +25V for QuickSilver models. If the system fails to start up, follow the procedure outlined below to determine whether the problem is related to the power supply. Note: To verify the power supply, you need a volt meter. VeriÞcation Procedure Follow the...