Stick 2 in slot 4 produced no errors for a full pass.
Put stick 2 in slot 1, about a thousand errors in the first few seconds.
Put stick 2 in slot 3, cleared a full pass, no errors.
Put stick 1 in slot 1, memtest wouldnt even get past "Measuring cpu/cache/mem speed..."...
Put stick 1 in slot 4...