Being unable to Prime95 even at stock would tend to indicate RAM issues (especially the large TFT or blended tests). That was one symptom of my first set of RAM for this motherboard being bad. Before I switched to these Mushkins which I like a lot.
Memtest only showed error on my old (Patriot) sticks in like 1 of every eight passes. But then they gradually got worse. Both sticks were bad as well. So the ol' "try one stick" method didn't work.
A few years ago, I had what seemed to be memory related problems, but they only showed up on Memtest weeks later. . . and then only when room temperature was over 85f.
Best,
H
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