A computer I built for a family member about 3-4 years ago suddenly had the integrated GPU in their i5 Haswell quit. Took a while to troubleshoot as I've hardly heard of the CPU still working, but only the GPU portion going dead. After a new motherboard and a out-of-the-parts-bin HD5xxx series GPU addition, everything seems to be working.
The preceding symptoms were video signal from the integrated GPU out cutting in and out over a couple of weeks. Then nothing.
How rare is it for the integrated GPU to die and the rest of the CPU to keep working?