RAM isnt tweaked. Or at least i dont think it is. And I've tried that, one memory, then switching them, to see if it was one specific memory that had the problem. But they both gave me the same error.
I can't really suggest an exact fix for this but I think you need to enter the BIOS and manually set the memory - you may first want to reset the CMOS.
The JEDEC SPD settings are the mobo default (both timings and voltage) - most performance RAMs these days are nowhere near the JEDEC SPD default so you have to manually set the timings and voltage.
And for uber-stability you should ungang the memory controllers - and disable spread spectrum.