What GPU, CPU and how much RAM does your computer have?
The upscaled textures are only slightly larger in file size than the previous textures (the full 34 patches with 1700+ textures is only ~2.6GB total), so to load ~3 textures in one window is at most 6-9MB more than it would have been previously which is a negligible amount to process.
Basically all that was done was taking 512x512/1024x1024/2048x2048 and scaling them up and defining details a bit more. The files are then compressed, so the actual size loaded is not significant.
EDIT: I will talk to Dragon, as we could potentially increase compression, and possibly re-add Crunch. The issue is that it significantly slows down the patch process, which was something we did not want to do.