Graham, On Sunday 13 March 2005 23:35, Graham Smith wrote:
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Quite often the problem occurs when the two RAM sticks have different timings. It is best to use RAM having the same manufacturer and chips or better still only have one stick of double the capacity.
The only universal advice, I'd say, is that you must understand the capabilities and limits of the memory controller circuitry as published in the board's technical reference. Modern systems use (or even require) RAM with SPD (Serial Presence Detection). SPD allows the RAM stick to tell the mainboard exactly how it should be accessed. The mainboard I use now can handle any old mix and match of RAM sticks (with some limits on the organization of DRAM chips on the sticks and on total installed RAM), but the more uniform their characteristics, the higher performance you get from the memory system. The manual describes a four-level hierarchy of decreasing uniformity of RAM stick characteristics (it has four levels because there are two slots each for the two channels, leading to four combinations of similarity / dissimilarity of the sticks installed).
Graham Smith
Randall Schulz