What type of RAM is used in the PowerBook G3 Series computer?
DISCUSSION
PowerBook G3 Series computers use SDRAM in a SO-DIMM slot which is smaller than the RAM slots for desktop Power Macintosh computers. There are two SDRAM SO-DIMM slots. One is located on the bottom of the processor card and the other is located on the top portion of the same module. The bottom slot is not customer accessible and RAM replacement or upgrades using this slot must be dealer installed. The top slot is user installable. For instructions on how to install memory in the top slot see the user manual for some models or the Help Center under the Help menu for other models.
PowerBook models ordered with extra RAM through the build-to-order (BTO) program (or CTO configure-to-order), the extra RAM will usually be installed in the upper slot, but can be installed in the bottom slot. This means that a PowerBook purchased through the BTO program may have both RAM slots populated.
To verify, check the Apple System Profiler under the Apple menu. In the Apple System Profiler go to the System Profile tab. Under this tab in the Memory Overview section look at the Built-in memory subsection for the location of any installed memory.
Third-party RAM is compatible if it meets the following criteria:
16, 32, 64, or 128 MB module (the PB G3 Series 1999 also supports a 256 module in the top slot).
1.0, 1.25, 1.5, or 2.0 inches in height (1.0, 1.25, 1.5 in the lower slot).
144-pin.
100 MHz or faster.
10 nanosecond or faster (a lower number is faster).
3.3 volt (V)
Unbuffered, 64-bit wide, with Serial Presence Detect.
The maximum amount of RAM supported in all PowerBook G3 Series except the PowerBook G3 Series 1999 is 192 MB. This can be achieved by installing a 128 MB module on the upper slot and a 64 MB module in the lower (dealer accessible only) slot.
The maximum amount of RAM supported in the PowerBook G3 Series 1999 is 384 MB. This can be achieved by installing a 256 MB module on the upper slot and a 128 MB module in the lower (dealer accessible only) slot.
Important:
The lower RAM expansion slot will only accommodate SO-DIMMs which are 1.0 through 1.5 inches in height. A 2.0-inch DIMM will not physically fit into the slot and cannot be used. EDO SO-DIMM RAM modules are not compatible with the PowerBook G3 Series. If you use an EDO SO-DIMM (from a PowerBook 2400, for example), the computer will start up fine but will not show any RAM increase in the "About this Computer" window.
Notes:
1. iMac RAM is compatible with PowerBook G3 Series computers.
3. For additional information on upgrading the memory, in the PowerBook G3 Series, read Knowledge Base article 25002:
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PowerBook G3 Series: Upgrading Memory
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Note:
Macintosh PowerBook G3 Series computers should not be confused with Macintosh PowerBook G3 computers. Though the names are similar, there are significant differences. For more information differentiating between the computers, read Knowledge Base article 24604: "
PowerBook G3, G3 Series: Identifying Different Versions
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