what is dram drive control?

i have the 8k3a+ motherboard..and i was wondering..in the ram settings of the bios, what is the DRAM drive control...and should i leave it on auto..or what.

I think its a kind of group with aggressive/default timings, that applies to all RAM settings.

I myself wonder what it actually DOES... but everything I've read says that setting this to high increases stability. I never noticed a difference. It's a stability option and not a performance option.