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Hardware Reference Guide
Hardware Upgrades
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contain the mandatory JEDEC SPD information
In addition, the computer supports:
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128Mbit, 256Mbit, and 512Mbit non-ECC memory technologies
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single-sided and double-sided DIMMS
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DIMMs constructed with x8 and x16 DDR devices; DIMMs
constructed with x4 SDRAM are not supported
Maximum operating speed is determined by a combination of the
CPU and type of memory used. Refer to the table below for the
optimum combination.
✎
The system will not start if you install unsupported DIMMs.
Single Channel and Dual Channel Modes
HP Compaq d228 and d230 Microtower models operate in single
channel mode. HP Compaq d248 Microtower models will
automatically operate in single channel mode or a higher-performing
dual channel mode, depending on how the DIMMs are installed.
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In single channel mode, the maximum operational speed is
determined by the slowest DIMM in the system. For example, if
the system is populated with a DIMM that is 266 MHz and a
second DIMM that is 333 MHz, the system will run at the slower
of the two speeds.
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In dual channel mode (d248 models only), all DIMMs must be
identically matched. DIMMs in the J23 and J24 sockets must be
identical; DIMMs in the J25 and J28 sockets must also be
Maximum Front Side Bus Operating Speed (MHz)
CPU Front Side Bus
(MHz)
DDR266
DIMM
DDR333
DIMM
DDR400
DIMM
400
266
266
266
533
266
333
333
800 (d248 only)
266
320
400
