Intel Core i3 9100 's Advantages
Released 6 months late
Integrated graphics card
Higher base frequency (3.6GHz vs 3.5GHz)
Lower TDP (65W vs 165W)
Intel Core i9 9900X 's Advantages
Higher specification of memory (DDR4-2666 vs DDR4-2400)
Larger memory bandwidth (85GB/s vs 37.5GB/s)
Larger L3 cache size (20MB vs 6MB)