It's a low quality commander core/cable issue and highly likely not firmware at all in most cases.
Lightly touching or even just moving the main large core cable whilst the red triangle shows (not recommended) seems to cause the display to change back and forth from the red triangle to the temp reading, show irregular random temp readings, or even stop cooling altogether, and for the cpu temps to soar. This seems to be heavily related to the main problem of the red triangle most have. A power issue related to the core or related cables.
Some people recommend to turn your system off and force the main cable that goes into the core hard until it clicks, try the cable at a different alignment so it doesn't fall out, or as a last resort even tie all commander core cables neatly together so there is little possibility for movement and a red triangle.
In the end though, I would not trust these coolers.
On some systems the h100i and 150i can have problems showing any alternative graphics on the display other than the default temperature readings, which seems to be a motherboard compatibility issue.
So all in all, the h100i and related range of coolers are a notable disappointment which should really have been taken back with replacements offered of entirely different models, rather than simply churning out identical models as replacements which at some point will likely show the same red triangle or display/cooling problems.
It's a shame really as most corsair products are generally of good quality, but I would have zero faith in their low to mid range aio coolers.
