Apple powermac g3 Service Manual
K
Service Source
Power Macintosh G3
All-In-One
K
Service Source
Basics
Power Macintosh G3
All-In-One
Basics Overview - 1
Overview
Introducing the Power
Macintosh G3 All-In-One
design.
• The new all-in-one is
designed for education and
fulfills all the computing
needs of teachers and
students.
• Powerful and easy-to-use
video editing and multimedia
authoring features at an
affordable price.
Click the icon at left for a
QuickTime VR movie of the
Power Mac G3 All-In-One.
Basics Overview - 2
Features of the Power Macintosh G3 All-In-One include
• PowerPC G3 microprocessor running at 233 MHz or
266 MHz
• RAM expandable to 384 MB in 3 DIMM slots using 64bit wide, 168-pin JEDEC-standard 3.3 V unbuffered
SDRAM DIMMs
• 512K of static RAM used as L2 cache on processor module
• Built-in 2D and 3D hardware graphics acceleration
• PERCH slot to support I/O card
• One modem slot on the I/O card for optional fax/modem
card
• 4 GB or 6 GB ATA hard drive
• 100 MB SCSI Iomega Zip drive
• CD-ROM ATAPI drive at 24X speed
• 1.4 MB SuperDrive
• One SCSI port
• Two GeoPort serial ports
• 10BASE-T Ethernet port
Basics Overview - 3
• One ADB port
• Three PCI expansion slots to accept
• three 7-inch PCI cards, or
• three 15 W cards, or
• two 25 W cards, or
• one 15 W card and one 25 W card
• Fan speed thermally controlled
• Energy Saver control panel
• 2 MB video RAM expandable to 6 MB with
3.3 V, 100 MHz or faster SGRAM on a 144-pin small
outline dual inline memory module (SO-DIMM)
Basics Overview - 4
Optional Build-to-Order Power Mac All-In-One Features:
• 100 MB SCSI Iomega Zip drive in the expansion bay
• 6 GB hard drive
• 64 MB (using one 64 MB DIMM) or 96 MB (using 1x
32 MB and 1x64 MB DIMM) of memory
• I/O, Audio/Video card
• 10/100 BaseT ethernet card
Basics The Cuda Chip - 5
The Cuda Chip
The Cuda is a microcontroller chip. Its function is to
• Turn system power on and off
• Manage system resets from various commands
• Maintain parameter RAM (PRAM)
• Manage the Apple Desktop Bus (ADB)
• Manage the real-time clock
Many system problems can be resolved by resetting the Cuda
chip (see Symptom Charts for examples). Press the Cuda
reset button on the logic board to reset the Cuda chip. (See
“Logic Board Diagram” later in this chapter to locate the
Cuda reset button.) If you continue to experience system
problems, refer to “Resetting the Logic Board” in this
Basics chapter.
Basics Resetting the Logic Board - 6
Resetting the Logic Board
Resetting the logic board can resolve many system problems
(refer to “Symptom Charts” for examples). Whenever you
have a unit that fails to power up, you should follow this
procedure before replacing any modules.
1 Unplug the computer.
2 Remove the battery from the logic board.
3 Disconnect the power supply cable from the logic board
and then press the Cuda Reset button. (See “Logic
Board Diagram” later in this chapter to locate the Cuda
Reset button.)
4 Wait at least 10 minutes before replacing the battery.
5 Make sure the battery is installed in the correct +/-
direction.
Basics Resetting the Logic Board - 7
6 Reassemble the computer and test the unit.
Note:
This procedure resets the computer’s PRAM. Be sure
to check the computer’s time/date and other system
parameter settings afterwards.
Basics Sound - 8
Sound
The sound system for the Power Macintosh G3 computers is
implemented entirely on the I/O card. Each supports 16-bit
stereo sound output and input, available simultaneously.
The sound circuitry on the I/O card and system software can
create sounds digitally and either play the sounds through
speakers inside the enclosure or send the sound signals out
through the sound output jacks. The sound circuitry digitizes
and records sound as 16-bit samples. The computer can use
22.050K or 44.100K samples per second. The sound system
plays samples at the sampling rate specified in the Monitors
& Sound control panel.
Basics Sound - 9
The Power Macintosh G3 also records sound from several
sources:
• A microphone connected to the line-level sound input
jack
• A compact disc in the CD-ROM player
• Analog sound from the cross-platform card in a PCI slot
• Analog sound from optional communication cards
• Internal Microphone
With each sound input source, sound playthrough can be
enabled or disabled.
Basics Sound - 10
Sound Output
All sound output features for the Power Macintosh G3
computer are provided by the I/O card. The I/O card
provides one mini jack for sound output on the back of the
enclosure.
The output jacks are connected to the sound amplifier. The
mini jack is intended for connecting a pair of headphones or
amplified external speakers. There are two speakers and two
headphone jacks on the front of the system. Inserting a plug
into the sound output mini jack disconnects the internal
speaker.
Basics Sound - 11
Sound Input
The I/O card provides a stereo sound input jack on the back
of the enclosure for connecting an external Apple PlainTalk
line-level microphone or other sound source pair of linelevel signals. The sound input jack accepts a standard 1/8inch stereophonic phone plug (two signals plus ground).
Note:
The microphone for the Macintosh LC and LC II does
not work with the I/O cards.
Options in the Monitors & Sound control panel determine the
interaction between the sound input and output devices. The
sound circuitry normally operates in one of three modes:
• Sound playback—computer-generated sound is sent to the
speaker and the sound output jacks.
• Sound playback with playthrough—computer sound and
sound input are mixed and sent to the speakers and sound
output jacks.
Basics Sound - 12
• Sound record with playthrough—input sound is recorded
and also sent to the speakers and sound output jacks.
Basics PowerPC G3 and Backside Cache - 13
PowerPC G3 and Backside Cache
Backside cache is a significant architectural design change
from earlier PowerPC processors. The main advantage of the
backside cache architecture is the speed of the dedicated
CPU-to-L2 cache interface. Using the dedicated bus allows
the CPU to access the fast L2 cache storage through a high
speed bus without addressing the slower system bus or
competing with other devices attached to the system bus. In
comparison, a “far-side” cache running on the system bus
would limit that SRAM interface to 50MHz.
The PowerPC G3 microprocessor interfaces with SRAM
storage via a dedicated bus running at various multiples of
the core PLL CPU speed. With high speed L2 SRAM and a
dedicated L2 bus, the CPU can access stored information up
to the speed of the processor clock. L2 access is determined
by the clock ratio setting. For example, with a 250MHz
Basics SDRAM DIMMs - 14
PowerPC G3, and a 2.5 L2 bus ratio, the backside cache bus
speed will be 100MHz, twice the speed of the system bus.
SDRAM DIMMs
Three DRAM expansion slots on the logic board accept 3.3 V
SDRAM unbuffered 8-byte DIMMs. The 168-pin DIMM has a
64-bit-wide data bus per bank. The minimum bank size
supported on the Power Macintosh G3 all-in-one model is 4
MB, and the largest is 64 MB. The largest DIMM supported
is a two-bank DIMM of 64 MB using 32 Mbit SDRAM
devices.
The Power Macintosh G3 All-In-One logic board supports a
maximum DRAM expansion of 384 MB. Fill all three slots
with 128 MB DIMMs.
Basics SDRAM DIMMs - 15
The DRAM DIMMs can be installed one or more at a time. The
logic board supports only linear memory organization.
Therefore, no performance gains are seen when two DIMMs
of the same size are installed. Any supported size DIMM can
be installed in any DIMM slot, and the combined memory of
all the DIMMs installed will be configured as a contiguous
array of memory.
Important:
DIMMs. DIMMs from older Macintosh computers are not
compatible and should not be used even though they fit into
the DRAM DIMM slots.
Power Macintosh G3 computers use SDRAM
Basics SGRAM Video Memory - 16
SGRAM Video Memory
The Power Macintosh G3 logic board comes with 2 MB of
Synchronous Graphic RAM (SGRAM) video memory soldered
on. The logic board also contains a video memory expansion
slot that accepts a Small Outline DIMM (SO-DIMM) to
increase video memory up to a maximum of 6 MB. Apple
supports a 4 MB SGRAM SO-DIMM that is 32-bit wide,
144-pin, fast-paged, 100 MHz/10 ns cycle time or faster.
Important:
or 512K video memory DIMMs used in older Macintosh
computers.
Use only SGRAM SO-DIMMs. Never use the 256K
Basics DIMM Slots - 17
DIMM Slots
DRAM
DIMM
Slots
Video Memory Expansion Slot
SGRAM SO-DIMM
ROM Slot
(Do not remove
the ROM DIMM.)
Basics - 18
Peripheral Component Interconnect
(PCI)
The Peripheral component Interconnect (PCI) expansion
slots accept 7-inch PCI cards. Install only expansion cards
that come with Macintosh drivers and are compliant with the
PCI 2.1 standard. Nubus™ cards cannot be used in these
expansion slots.
PCI offers significantly higher performance than the NuBus
architecture used in previous Macintosh models. Running at
33 MHz, the PCI bus is up to three times faster than NuBus,
offering overall enhanced system performance, particularly
in the areas of video and networking.
Basics Internal Locator - 19
Internal Locator
Video Board
Analog Board
Zip Drive
Logic Board
CD-ROM Drive
Hard Drive
Power Supply
Floppy Drive
Basics Rear View - 20
Rear View
SCSI
Port
Apple
Desktop
Bus
(ADB)
Port
Sound Output Port
Ethernet
(10Base-T)
Port
Printer
External
modem
Port
&
Monitor
Port
Sound Input Port
Card
Port
Access
Covers for
Expansion
Slots (3)
Internal
Modem
See next page for
optional AV card.
Basics Optional AV Card - 21
Optional AV Card
Audio output ports
(right & left)
Composite Video Ports
(OUT and IN)
Sound Output Port
Audio Input Ports
(right & left)
S-Video Ports
(OUT and IN)
Sound Input Port
Optional AV ports
Basics Logic Board - 22
Logic Board
Power Supply
Jumper Block
Cuda Reset Button
PERCH
Slot
Ethernet
Port
Monitor
Port
Serial
Ports
ADB
Port
SCSI
Port
Internal SCSI
Connector
IDE Connector
PCI
Slots
Video Memory
SO DIMM
Voltage Regulator
Processor Jumper Block
Battery
LED
Speaker
Power
On/Off
CD
Audio
ROM
DIMM
DRAM
DIMM
Power Supply
Connector
Floppy Drive
Connector
Microprocessor
Basics Repair Strategy - 23
Repair Strategy
Service the Power Macintosh G3 computers through module
exchange and parts replacement. Customers can request onsite service from an Apple Authorized Service Provider Plus
(AASP+), Apple Assurance (US only), or Apple Canada
Technical Answerline (Cananda only). They can also choose
carry-in service from an AASP.
Ordering
Apple Service Providers planning to support the computer
systems covered in this manual may purchase Service
modules and parts to develop servicing capability. To order
parts, use the AppleOrder (US only) or ARIS (Canada only)
system and refer to the Power Macintosh G3 “Service Price
Pages.”
Basics Repair Strategy - 24
Large businesses, universities, and K-12 accounts must
provide a purchase order on all transactions, including
orders placed through the AppleOrder (US only) or ARIS
(Canada only) system.
USA Ordering
US Service providers not enrolled in AppleOrder may fax
their orders to Service Provider Support (512-908-
8125) or mail them to
Apple Computer, Inc.
Service Provider Support
MS 212-SPS
Austin, TX 78714-9125
For US inquiries, please call Service Provider Support at
800-919-2775 and select option #1.
Basics Repair Strategy - 25
Canadian Ordering
Canadian Service providers not enrolled in ARIS may fax
their orders to Service Provider Support in Canada (1800-903-5284). For Canadian inquiries, please call
Service Provider Support at 905-513-5782 and select
option #3.
Basics Warranty/AppleCare/ARIS - 26
Warranty/AppleCare/ARIS
US Only
The Power Macintosh G3 computers are covered under the
Apple One-Year Limited Warranty. The AppleCare Service
Plan is also available for these products. Service Providers
are reimbursed for warranty and AppleCare repairs made to
these computers. For pricing information, refer to “Service
Price Pages.”
Canada Only
The Power Macintosh G3 computers are covered under
AppleCare. The Extended AppleCare Service Plan is also
available for these products. Service Providers are
reimbursed for warranty and AppleCare repairs made to
these computers. For pricing information, refer to “Service
Price Pages.”
K
Service Source
Specifications
Power Macintosh G3 All-in-One
Specifications Introduction - 1
Introduction
Specifications information for this product can be found in the Spec Database, which you
can access at Service Source Online (http://service.info.apple.com) or on Service Source
CD.
Spec Database at Service Source Online
From the Service Source Online home page, click Troubleshoot and Repair to access the
main repair procedures page. Then click either Apple Spec in the navigation table in the
upper right corner of the page, or click Apple Spec Database from the list of reference tools
below.
Spec Database on Service Source CD
Open the CD and double-click the Apple Spec Database alias located at the top level of the CD.
Loading...