I have multiple monitors from different manufacturers. The setup I have completely breaks screen blanking for energy saving. I've spent over two years on this issue now and I'm pretty sure it's hardware related on the monitor side. When power saving is enabled, despite two years of research, the screens power back on almost immediately, never staying off for more than a second or two. I'm poor and can't afford new ones, so my solution is to... use a blank screensaver instead to save my screens from burn-in.