Memory Subsystem - HP Compaq d330 DT Technical Reference Manual

3.3

MEMORY SUBSYSTEM

These systems feature a dual-channel double data rate (DDR) SDRAM subsystem that accepts
PC2100, PC2700, and PC3200 DIMMs.
NOTE: The DDR SDRAM "PCxxxx" reference designates bus bandwidth (i.e., a
PC2100 DIMM can, operating at a 266-MHz effective speed, provide a throughput of
2100 MBps (8 bytes × 266 MHz)).
NOTE: Memory speed types may be mixed within a system, although the system BIOS
will set the memory controller to work at speed of the slowest DIMM.
These systems accept DIMMs with the following parameters:
♦ Unbuffered, compatible with SPD rev. 1.0
♦ 32-, 64-, 128-, 256-, and 512-Mb memory technology
♦ Single or double-sided
♦ Non-ECC memory only
The SPD format supported by these systems complies with the JEDEC specification for 128-byte
EEPROMs. This system also provides support for 256-byte EEPROMs to include additional
Compaq-added features such as part number and serial number. The SPD format as supported in
this system (SPD rev. 1) is shown in Table 3-3.
The key SPD bytes that BIOS checks for compatibility are 2, 9, 10, 18, 23, 24, and 126. If BIOS
detects EDO a "memory incompatible" message will be displayed and the system will halt.
These systems are shipped with non-ECC DIMMs only. Refer to chapter 8 for a description of
the BIOS procedure of interrogating DIMMs.
NOTE: These systems are designed for using non-ECC memory only. The system will
not boot if the BIOS detects an ECC DIMM.
An installed mix of DIMM types (PC2100 and PC2700, CL 2 and CL 3) is acceptable but
operation will be constrained to the level of the DIMM with the lowest (slowest) performance
specification.
If an incompatible DIMM is detected the NUM LOCK will blink for a short period of time during
POST and an error message may or may not be displayed before the system hangs.
hp compaq d330 and d530 Series Personal Computers
Featuring the Intel Pentium 4 Processor
First Edition - June 2003
Technical Reference Guide
3-5