Re: S2721H, display is going to sleep in 4 minutes

I solved (or worked around the issue) by buying an HDMI cable of a better quality and the problem is now gone. The monitor is going to sleep as it should.

Diagnosing the difference between the two cables, I found out that the cheaper cable did not have all the grounding pins connected, but the more expensive cable had all the wires connected internally. It seems that the Dell monitor is really picky and do not accept HDMI cables which do not have all the wires wired properly.

I do not know any other monitor brand that does this.

But at least now with the new cable all works as it should. Hope this helps someone!