Just to let you know updating sorted my problem right out. However... It has left me with a far more frustrating problem. Now somewhat randomly when I disable the f.lux (so "disable until sunrise") and then reduce the brightness of my screen using Alt+PgDn my screen return to full brightness and I can't work out why. If I then press Alt+PgDn again it dims to the previous level , rather than one less than normal. So i go from 82% brightness (the setting of my display), down to say 25% using Alt+PgDn, it then jumps back up to 82% and if I press Alt+PgDn it doesn't go to 76% (the setting one below 82%) but rather straight to 25%. The interval of the brightness jump seems to be random and it only ever increased brightness not decreases. I've completely uninstalled and re installed f.lux to try and fix it, no help. Honestly I'd rather go back to v4.55 as that issue was far less annoying!

You can use Alt+Shift+Page Down to go to 800K.

@Casey-Ryback How-To Guide: https://mirillis.com/en/products/tutorials/action-tutorial-intel-quick-sync-setup_for_desktops.html#top

@Tungsten_smooth said: @lavacano201014 Do you just have one video cable in only one card? Two video cables, technically, but both on one card (and half the time the second monitor isn't turned on anyway). I haven't tested to see if unplugging the disabled monitor has any sort of effect, but the monitor itself doesn't cause the second card to wake. How are you checking wake levels? A couple different things happen when the second card turns off: OpenHardwareMonitor stops reporting certain sensors on that card. Specifically, it reports the temperature as "0.0 C" and the clock speeds as "-" More interestingly, the great big LED logo on the side of the card stops glowing, and the fans stop spinning. @herf said: Does "Safe Mode" help? No.

@onotole f.lux actually modifies this setting for activation at sunset. Then I assume it sets the "dark theme" back to unchecked, once sunrise happens. It's probably enabled by default in f.lux, so look in the settings there first.

@oschlag Ah, sorry for making this duplicate thread then! Thanks for the link.

Same here on Z1 Compact 5.1.1 Lollipop. If I wait long enough and mess around with locking/unlocking the phone, the black screen goes away and I can use my phone again. Other than that (and the known issue when f.lux gets disabled for a second when an app is installing/updating) it's been working great!

@Adam-Michael-Sasine Make sure you have "automatically adjust brightness" in Display system preferences turned off. Other than that I don't know, but in an emergency you can run RedScreen for Mac OS. You have to quit f.lux first, otherwise exactly the same thing will happen! It can be a symptom of two different things trying to adjust the screen at the same time.

@Tungsten_smooth said: @Gentz Now you can open the magnifier and invert the colors (ctrl alt i). I think it's the APU not understanding the color inversion part. Yeah, something somewhere is definitely not allowing f.lux to work correctly. :/