It is not technically a good idea to disable integrated graphics. There are a variety of reasons for it. If your system doesn’t have a dedicated GPU, it is highly recommended not to disable the integrated graphics. This is because your system will then resort to handling graphics-related tasks by software rendering. Software rendering puts a major toll on the performance of the system as now the CPU has to handle all other system tasks and programs along with software rendering which consumes a lot of CPU time. Thus the system slows down significantly and no work can be accomplished on time. Another problem that’d arise would be the display of the system. The user interface will be choppy and the resolution of the screen reduces by a lot.   Another reason why it’s not a good idea is for Laptop users. Disabling iGPU in laptops affects screen resolution and proper functioning of the user interface even while having a dGPU present in the laptop.