2 System Board
Chip-Set
accesses to related addresses, they do not need four independent accesses to main memory, but can be organized as a pipelined burst. The second, third and fourth cycles in each burst require less time to complete than the first. This is because the first cycle includes the addressing phase and memory
There are two programmable
Main Memory Controller The main memory controller supports up to 512 MB of main memory (dynamic random access memory, DRAM), arranged in banks of any mixture of memory capacities, provided that each bank contains a pair of identical single interline memory modules (SIMMs). The HP Vectra VL 5/
xxxSeries 5 and XA 5/xxx PCs have provision for three banks. With the 32 MB module from HP, this gives a total capacity of 192 MB. With a future 64 MB module from HP, it will give a total capacity of 384 MB.
In the case of 66 MHz PL bus operation, memory accesses have a timing pattern of
The controller supports relocation of system management memory. It supports a read cycle power saving mode, and a CAS before RAS Intelligent Refresh mode of operation, with a CAS# driving current that is programmable.
The controller is fully configurable for the characteristics of the shadow RAM (640 KB to 1 MB). It supports concurrent write back. To implement the optional error correcting code (ECC) or parity checking,
1.As used for the HP 512 KB cache memory module.
2.As used for the HP 256 KB cache memory module.
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