NVIDIA GeForce GTX 860M 's Advantages
More VRAM (4GB vs 2GB)
Larger VRAM bandwidth (80.19GB/s vs 14.40GB/s)
384 additional rendering cores
NVIDIA GeForce 830A 's Advantages
Released 6 months late
Boost Clock has increased by 6% (1150MHz vs 1085MHz)
Lower TDP (33W vs 75W)