I also had a lot of problems with stak-amd... I'm using 8xVega64 and after a while with stak-amd one card goes to 0h/s and then the whole rig just shuts down. I switched yesterday to cast-xmr, it seems more stable and until now I had no crash/shut down. I also noticed if I'm connecting with teamviewer or opening some applications like GPU-Z, the cards are starting to mine with a lower hash rate same like the HBCC was deactivated.
Exactly my issue. One card hangs then the rig follows shortly after.I also see that any diagnosing utility must be started beforehand or it takes forever to launch and has a high probability of hanging the rig.
Castxmr seems less susceptible to this compared to stak-amd.
Like I said, lowering the speeds of HBM does not help. I go as low as 900 and still hangs. BTW, I'm using sapphire bios. Might be that it's not the same as other makes (gigabyte/msi etc).
One thing I noticed, is stakxmr uses a little more power per card (about 5W).
Running out of ideas to try.
I also use Sapphire cards and yes stak-xmr uses more power than cast-xmr, I noticed also
If you lower the speed of HBM it's useless. I found why my rig was shutting down (I think), I changed the power plan, monitor -> turn off - never; HDD -> turn off - never, and so on... Without these setting many times after 30 - 60 min since I closed the connection thru teamviewer, my rig either was shutting down or froze. I see now it's working, hope this was the issue.