But if you look at page 12 of the manual, it also says it is 4k..
But our discussion is just academic if it is not for sale.
Yup, we will know the true specs when the monitor is officially released. Not to say that you are wrong, but I stand by my understanding that the S2718H/S2718HX monitor is physically a Full HD monitor that somehow accepts a UHD input (4K) through a HDMI 2.0 cable. I do hope that I am wrong, because that would be a really cheap price for a 4K monitor.
The reason why I say that it's a Full HD monitor is simple.
1. Price - My current LG 27UD88 4K monitor costs $865. The similarly specced 27" Dell IPS 4K monitor also cost around $849. Therefore, this led to my doubt about the $359 S2718H monitor being a full 4K monitor.
2. The manual listed that the Pixel Per Inch (PPI) of the S2718H monitor is 81. A true 27" 4K monitor would have PPI of 163, whereas a true 27" Full HD monitor would have a PPI of 81. This would suggest that the S2718H is physically a Full HD monitor.
3. The monitor would accept a 4K input only under special circumstances, that is OSD Movie HDR or Game HDR. To be honest, I have no idea what is Movie HDR or Game HDR, but under normal windows settings, the maximum resolution is 1920 x 1080 as listed in the manual.
TL;DR Price is too low, PPI is too low to be a real 4K monitor. Of course, I hope to be proven wrong.
This is all my humble opinions. My advise is to wait for the monitor to come out before deciding to drop the money on it. There are also a few threads on other forums debating about this, like
here and
here, if anyone is interested.