If you set the timings lower manually, say from 2.5-3-2-5, to 2-3-2-5, is this "overclocking" the memory? What are the effects of doing this, any dangers, stability issues, etc? Also what is "spd" - speed? or what does that stand for?
Also, if I use a memory divider; running 220mhz HTT and 200mhz Memory, is my memory now a bottleneck/bandwidth limiting my CPU... or what is happening here?
Yes, that is 'overclocking' the memory. It is unlikely to physically harm the memory if the timings are too tight, but it can be unstable and crash the system.
SPD = Serial Presence Detect. Its a few bytes of non-volatile memory (like Flash RAM - maybe it is flash, I don't know) that stores the mfg's settings for RAM timings.
On AMD's the bottleneck from using a memory divider results in about a 1% performance loss (for RAM from 200 to 166). So, if you would get 100fps in a game, you may get 99fps because your RAM is running on a divider. Usually, that's not even enough difference to notice unless you're benchmarking.
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