Timing Question

[Iced]

Hello,

I recently posted a question to try and get my F2-8500CL5D-4GBPK working with my ASUS M3A78-EM and eventually settled on a configuration (thanks gskill techs)

Can someone willing explain why my DDR2-1066 5-5-5-15 would actually be slower than configuring it to run as DDR2-800 4-4-4-12?

Thank you,
--Iced

[GSKILL TECH]

The memory controller (CPU-NB) is on the CPU. The CPU-NB drives the memory. AMD designed the CPU for DDR2-800, so the maximum NB bandwidth from factory is only for DDR2-800. As a result, if you don't overclock the CPU, DDR2-1066 won't be much faster since the CPU is restricting it. With the memory at DDR2-800, you are using full NB bandwidth, AND the timings are lower than standard. As a result, it is the best configuration for AMD CPUs. For even better performance, some people try to lower timings or raise frequency slightly higher, and that will give you the max performance (especially for gaming).

Another thing is, it requires over voltage for the CPU-NB to support a higher memory frequency. This means more stress on the CPU-NB. This is the reason DDR2-1066+ can be somewhat difficult as most don't want to tweak voltages. Instead of pushing the CPU to do something greater than it was made to do, we are maximizing what it is capable of doing.

Hopefully that makes sense.

Thank you
GSKILL TECH

[Iced]

Thanks

Thank you for the reply! I did some more reading here after I read your description. Makes sense on how/what I can fiddle with now.