If you want something more relevant thats actually better than the i7 at maybe a similar price then look at x79/99 workstations, maybe you can find a cheap one and drop an e5 1650 or one that already has a 1650/1660 in and overclock to 4ghz via throttlestop, also quad channel so lo...
In your case the GTX1650 is not powerful enough for 4K and doesn't have enough vram buffer to hold all the textures in it to get consistent fps .. try half-life or half-life 2 in 4K or some games like OpenTTD or platformers and you should get easily 60fps and good compression rat...