amd expo is covered by warranty. expo also does not overclock the cpu. that amd expo changed cpu voltage was a decision by asus, not by amd, the asus implementation is basically not up to spec.
Overclocking RAM involves overclocking the memory controller which resides in the CPU.
AMD themselves also make it clear that users who overclock "assume all risks and liabilities that may arise out of overclocking and/or undervolting AMD processors" per the footnote on their EXPO page.
Overclocking will void warranties, this is a fact that anyone who wants to overclock has to accept. AMD should be ashamed for hiding the literature behind a hidden footnote, but that doesn't excuse end-user ignorance.
expo won't void warranty. amd replaces expo'd processors. they make advertisments with expo. in the eu/uk they would not stand a chance to refuse any rma whatsoever when expo was enabled.
