Ignore GPUcheck. Ignore any and all websites that claim to give a) automated comparisons of X vs Y and/or b) give bottleneck ratings as a percentage / 'calculate' your 'bottleneck'. While it looks like a nice, easy answer, it's junk piled on top of junk. Which is unfortunate because they come up high on google results.
Also it depends a lot on what games you play, and what settings you find acceptable. A 1650 is a very good entry level gaming GPU.
While bottlenecking is an overused term, it's valid to talk about it here.
There are 2 issues: 1) can your CPU be a bottleneck? 2) does it really matter?
The answers are 1) yes, sometimes and 2) no, not really.
This article explores bottlenecks with a similar CPU (2 cores, 4 threads, like your i3) and graphics cards in the same ballpark as the GTX 1650 (things like the RX 570 for example) to show where bottlenecks can appear.
The main conclusion is that you can still do fine with a 2-core, 4-thread CPU and an entry level GPU.
The next question was how good of a GPU can be paired with the G4560. Someone buying a $70 CPU won’t likely be buying a GTX 1080 – and probably not a 1070 – but we wanted to see how far up the scale we could go before encountering a CPU bottleneck. -
It's three years old, though GPUs like the RX 570 it examines are still mainstream. Obviously some modern titles like Assassin's Creed Origins/Odyssey would probably change the picture a bit as they are brutes and very demanding on the CPU.
In some games, depending on your settings, your older i3 CPU would be a problem for performance, at least some of the time. You could expect framerate drops and a less smooth experience in those titles.
However, in general, a GTX 1650 is still going to be a massive
upgrade on your GT 640. Orders of magnitude better. And in most games, you'll get your money's worth from the upgrade.
I can't tell you about Ark specifically, only that Ark can make use of a powerful graphics card from what little I've played it, so you should expect a big improvement in average framerates and the kinds of settings you can run the game at versus your GT 640.
The GTX 1050 ti is a last generation GPU that is weaker than the GTX 1650. If those are the prices, go for the 1650 without hesitation.