Did Ryzen master crash or the whole thing? To me it looks like you have them running at 6000, but maybe not stable? However if you're also tweaking things in Ryzen master it is difficult to know what is causing your instability. I'm a few generations behind but the situation you're describing with PPT does not seem to be RAM related at least on the surface.
With just expo set in the bios and all four sticks installed, is the system stable?
A lot of overclocking is not set it and forget it, although EXPO is an attempt at this, its important to remember that it's not just the RAM but also the memory controller (which while located on the physical CPU, is not part of the core and is actually on a separate piece of silicone and not to my knowledge a significant component of PPT, or the chip's power draw) that has to operate beyond spec. Double the memory sticks is double the work for the controller. I would check your temperatures as a sudden drop in power is more consistent with a thermal problem in my experience.
This is why any tweaking or overclocking often requires a systematic approach, especially in troubleshooting. You'll want to establish that the system is stable/functional, make one change, and establish again that it is stable before making additional changes. If you change everything all at once, you won't know where things went wrong. Some people use stress tests (I think OCCT is a good one these days and has a pretty functional free version), but others chose not to, because the stress test goes beyond normal use. But if you want to *know* if a setting is stable, then move on, to the next setting, then retest, this is the way to do it.
If you're system is currently unstable, you should go into the BIOS and reset factory defaults. Then establish that it is stable at default settings (either through normal use or a stress test, your preference - either way each step of stability can take hours to days depending on the stress test or use case). Once you are comfortable that it is, you can enable EXPO and try again. If it's not stable, you can try to adjust some timings to achieve a stable setting, or in some generations minor adjustments to certain voltage settings can help (I'm not sure if this is the case for the 7000 series, you'd have to ask someone more up to date). I don't think the x3d chips allow for much in the way of overclocking or tweaking anyway now that I think of it.
