Normally, you want a balance of cpu and gpu resources for gaming.
If your games are sims, mmo, or strategy games, then fast single thread processor is best.
A lesser graphics card can still do well.
If your games are fast action games, then the graphics card is all important.
If you play multiplayer games with many participants, then a high thread processor like the 3800X is good.
If you wanted a simple rule of thumb for a balanced gamer, it would be to budget 2x the cost of the processor for the graphics card.