You're clearly not stable considering you got a huge rounding error in prime in under an hour based on what I'm seeing there, although you wanna run the torture test with large in place FFTs for better results
Either way you have some work to do, I have no idea what steps you took to get those initial results so I have no idea how stable that really is, however you need to run prime for about half an hour everytime you bump up clock frequency and if it fails, you have to bump up vcore until it passes through
If you don't wanna overclock you ram, you'll have to lower your divider again to keep your memory frequency below 200mhz