which is a pretty big jump! And note that, every time you swing your view around to something with completely different textures (say, from a forest to the desert behind you) the video card will have to either already have those textures cached (which is less likely the more space each needs) or have to load them from RAM or disk, which introduces camera lag. Now if you step up to a 128x128 texture pack, that's going to (for that particular angle on that particular forest) load 20MB*4*4*4 of texture data over the 16x16 version, for 1.28GB of VRAM needed. So what this math means is that if your GPU is using (for example) 20MB of its onboard VRAM for storing the textures for a particular scene (i.e., looking at a particular forest) using a default 16x16 resolution texture pack, going up to a 32x32 texture pack will require 80MB of VRAM for looking at that spot from that angle, and the card has to spend proportionately more time to render it all.* Jumping up to a 64圆4 texture pack will increase it again to 320MB of texture memory needed. This is all also stored in RAM too, but your RAM is rarely the performance bottleneck when increasing texture size. Every 2x texture size step (16 to 32, 32 to 64, etc.) involves 4x the GPU processing* than the previous step. Resource packs that provide high-resolution textures ('HD texture packs') require your GPU to fetch, store, and render exponentially more pixels every frame.

What is a resource pack for minecraft