Start at mining only one GPU installed in PCIe x16 slot, and set aside or exclude all other GPU's for the meantime.
If this runs successfully, you may now install other GPU's one by one, from there you can actually troubleshoot which might be the culprits.
It maybe a Riser, PSU, Drivers, etc.
I can try that, but what will I learn? The system runs stable for 24+ hours if I don't modify the GPU settings or if I modify the settings using Afterburner. But putting those same settings in the Claymore config causes a crash on startup.
Doesn't the fact that I can run stable with no GPU modifiers (or modifying GPU with Afterburner) indicate that hardware and drivers are working correctly?
- Dave
It is a fact that when you do OC settings you are adding power and stress to the card, and most likely your hardware cound't handle it. with the steps I posted you could probably get an idea on why a single Card (assuming it runs successfully) with OC settings or vice versa (Assuming it failed)