Hardware acceleration using GPUs does not seem to improve texture rendering performance, for example at 300 dpi or higher raster render quality, the UI lags a lot for complex files.... Same is the case for effects such as blur, glow etc. GPUs are much more capable in rendering than CPUs and Illustrator doesn't seem to take advantage of their rendering power. For example it lags on a GTX 1070 with an 8 thread CPU once you start using raster effects/textures. Please improve texture/raster effect performance using hardware acceleration and optimisation for multithreaded systems.