Hardware Reference
In-Depth Information
Memory modules of each type and capacity are available in various speed ratings. Consult your
motherboard documentation for the correct memory speed and type for your system. If a system
requires a specific speed memory module, you can almost always substitute faster speeds if the one
specified is not available. Generally, no problems occur in mixing module speeds, as long as you use
modules equal to or faster than what the system requires. Because there's little price difference
between the various speed versions, I often buy faster modules than are necessary for a particular
application, especially if they are the same price as slower modules. This might make them more
usable in a future system that could require the faster speed.
Because SDRAM and newer modules have an onboard SPD ROM that reports their speed and timing
parameters to the system, most systems run the memory controller and memory bus at the speed
matching the slowest module installed.
