I played games that looked almost exactly like this about 25 years ago,
with an AMD K6/2-450MHz with 256 MB RAM and a Matrox Millennium.
Why do you need an up-to-date gaming computer for a game like this nowadays?

If the minimum requirement for the graphics is a GeForce GTX 660,
then the game (Kubikon 3D) will not(!) work with...

GeForce GTX 750 Ti
Radeon HD 7790
GeForce GT 1030
Radeon RX 550

This game will not work
with an "integrated graphics unit".

Hi there. I'm a solo developer and when writing down the minimum requirements I want to put something relevant there. I can't test the game on all low spec PCs, so I can't really be sure what the lowest possible spec is to run the game. The GTX 660 is a 12 year old graphics card that was in one of my old computers. If you want to be sure how the game will work for you, you can try it and then just refund if it does not work for you. GOG has a very generous refund policy. Thank you very much.

Do you think GOG will give me my money
back if I buy a game they warn me not to buy?
I am running MX-15 Debian Jessie 32 bit
on a 15 year old computer with 2 GB RAM
and currently a GeForce GT 710.
At the time, the GeForce GTX 660
was a graphics card for power gamers. And
it is still more powerful today than some newer
graphics cards suitable for gaming. But I don't
think that a game of this kind really needs this
kind of performance. Many GeForce GT 710s
are installed or sold. Why not just buy one
second-hand and test it out? Does the game
work with the Intel i3-3220 if you remove
the graphics card? The Intel i3-3220 comes with
integrated Intel HD 2500 graphics.
If your game is level-based why don't you offer
a demo version that contains a few levels?