Hi, as far as I've been able to test, it's not a mod related issue because the same version of all the software in a far better and newer pc work perfectly.
In my MC, villagers, illagers, all "humanoid mobs", animals (vanilla and modded (geneticanimals, exotic birds and alexmobs) get glitched. The glitch varies depending on the shader. With Sildurs Vibrant Shaders v1.283 Lite all the npc and mobs looks transparent. With MakeUp-UltraFast-4.03beta, VPlus_v2.3a, BeyondBeliefLegacy_V1.2.0, BSLex_(BSL_Edit)_By_LexBoosT_V7.8.3 and other, npc and mobs look black or partially black or with protuberances XD
Now, on previous versions of the game, I've used shaders with this same computer, but with half of the RAM I have now. Since the problem persist with all the shaders, I think is my gpu, but I know nothing about this and maybe someone could give me a fix because right now I'm not able to buy a better gpu or anything else... I would appreciate any help you could provide.