This issue seems to be tied to the display powersaving tech that Intel has called Panel Self Refresh, which may cause the display panel to not update in certain situations (though it's not good at figuring out what those situations are) to reduce power.
I've fixed it on my SP7 i5/8G/256G by installing the Intel Graphics Command Center from the Microsoft Store, opening it, going to System>Power>Panel Self Refresh and turning it off for both "On Battery" and "Plugged In".
FANTASTIC... I had this issue on my SP7 / i7 / 16GB and upon installation of Intel Graphics Command Center and turning off Panel Self Refresh my SP7 does not freeze or does not blackout. Its been 24 hours now and it hasn't occurred so far. Thanks for this wonderful, useful tips.