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I am researching single board computers with the hope of designing on at the end of this, I am at the stage of DDR3, but can't find any good info on routing ddr3, regarding what traces need to be matched, and so on. Which traces need to be matched? I am assuming it's the DATA traces, and any traces that take data that needs to be in sync, would I be correct in thinking this? Or would it be better to match them all to avoid the chance of missing something or running into issues.