I'd made precisely one change to the config on the XPS9370; which was to add deep sleep to the kernel boot parameters for grub, vis.
``` GRUB_CMDLINE_LINUX_DEFAULT="splash mem_sleep_default=deep" ```
as otherwise this device didn't always sleep on lid close. I'm going to revert that (and pay attention to the hot laptop) and see if it happens, though I appreciate it won't be a huge step forward in narrowing this down.
I'd made precisely one change to the config on the XPS9370; which was to add deep sleep to the kernel boot parameters for grub, vis.
``` LINUX_DEFAULT= "splash mem_sleep_ default= deep"
GRUB_CMDLINE_
```
as otherwise this device didn't always sleep on lid close. I'm going to revert that (and pay attention to the hot laptop) and see if it happens, though I appreciate it won't be a huge step forward in narrowing this down.