What are the specs of those systems with integrated GFX?
RAM configuration, size, CPU L3 cache size, no. of cores and iGFX turbo frequency - all that matters for precise evaluation. Simply stating "weaker intel chips are not appropriate to run GTA V" isn't quite doing it its justice. :o
HD4000 can outperform easily even today's low-end dedicated ones (HD7570M), BUT only on quad-core systems with 16GB dual-channel memory and clocked on 1300MHz. :)