Check your manualThere is a diagram a few pages in listing what is what. The 3 and 4 pin fan headers are listed as CPU fan headers, where the fan header near the 8 pin ATX connection is listed as the power fan connector (PWM). For stability I run BOINC, specifically, SETI to check for stability. I just load up a bunch of SETI tasks to make sure all 4 cores are 100% loaded and let it run while I do other general day to day stuff on the system. I use HCI memtest to check the stability of any memory OC and I sometimes use IBT w\ AVX using the maximum amount of memory my system has available.
Check MMIO is indeed 1024, but even with it set at 64 its not going to do any harm. Correct voltage for your memory should be applied by default without having to load the XMP but this will depend on the speed data the manufacturer has pre-programmed to the memory modules, so setting the voltage manually might be required.
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