Question Faulty RAM, and default RAM speed anomaly ?

[joerack]

It appears I have some faulty RAM (windows exception fault + memtest >800 errors).

But there is one thing I specifically do not understand: Why does my (faulty) G.Skill ddr4 3200mhz default to 2133 while my crucial 2400mhz defaults to 2400?

 

[popatim]

3200 is an overclocked (XMP) speed with 2133 probably the default (SPD) speed. And it sounds like the Crucials SPD speed is 2400.

 

[joerack]

I tested with memtest86 my old crucial (stock speed) and even that is erroring out with memtest. Welp. 4 faulty modules? hard to believe
I will now test all 4 on my old a320m-k. (4hrs test each). Could it be a motherboard issue ?