A few options, if you really want to upgrade:
BUT, these (CPU's) are not really upgrades when only looking at 4K gaming.
Get a 2x16GB DDR4 3200 or faster kit AND a nice 2TB PCIE4 Gen 4 NVME or go hog wild with a nice 4TB SATA SSD.
3700X
5600X
10700 non K, as it will perform like a 10700K when power limits are removed.
"In practically all of our tests, the Core i7-10700K is ahead by a super slim margin. At $387 for the 10700K compared to $335 for the 10700, the performance difference is not enough to warrant the $52 price difference between the two. Performance per dollar sides mostly with the Core i7-10700, although users getting the i7-10700K will likely look towards overclocking their processor to get the most out of it – that ultimately is what to pay for.
The other comparison point is with the Ryzen 5 5600X, which has two fewer cores but costs $299. In practically every test, the increased IPC of the Ryzen over Intel means that it sits identical with the Core i7 processors, AMD is cheaper on list price, and at a much lower power (AMD will peak around 76 W, compared to 215 W). AM4 motherboards are also abundant, while corresponding Intel motherboards are still expensive. The problem here however is that AMD is having such high demand for its product lines right now that finding one in stock might be difficult, and it probably won’t be at its recommended price.
Users in this price bracket have a tough choice – the more efficient AMD processor that might be in stock, compared to the Intel processor that will be in stock but more cooling will likely be required."
Use AT bench to compare and contrast, figure a budget and go from there.
Here is 9700K vs 10700 non K
CPU 2021 benchmarks: Compare two products side-by-side or see a cascading list of product ratings along with our annotations.
www.anandtech.com