I have set my computer to put the monitor into standby mode after 10 minutes of inactivity - during which my monitor is still powered on but the PC shuts off the video. To wake it, usually bumping the mouse or pressing any key/button will wake it. I have found recently that sometimes it won't come out of standby. Moving the mouse won't wake it, hitting keys won't wake it, it just remains in standby mode - the PC is still on and running but the display won't wake. My monitor has two power switches - kinda like a PS2 or PS3, it has a toggle switch I/O on the back of the unit that must be flipped to the "On" position and then you can push the button on the front to turn it off and on. What's most peculiar is if I push the power button on the front of the monitor, wait a second, then turn it back on - I hear my video card fan cranking up to 100% (idle speed is about 40% but I can tell that it's running at 100% when I do this). I have two GTX 260's in SLI and only one of them is doing this (my primary which is the one the DVI is plugged into). After a few seconds it goes back to idle speed, then the monitor continues flashing as if it's receiving no image at all. I can repeat this as many times as I want by turning the monitor off and then back on as well. The only way to fix the computer when it does this is hitting reset - after which everything works just fine.
I do not understand this at all. I'd normally suspect overheating, but A) My computer is idling doing nothing, and B) The primary card is the most well ventilated of the two hence why it's the primary one, it has plenty of air flow via several 120mm fans in my case. It's stupid because this happens randomly - plenty of times my computer will put the display into standby and I can wake it with no problems. I'm using Win 7 Pro 64-bit should that matter. I have the latest Nvidia drivers installed, no extra video card programs running or anything - just EVGA Precision tune to monitor my temperatures, I don't use the overclocking portion at all. What is the problem here? Anyone have any thoughts as to what it could be? It's driving me crazy and like I said only started recently. I prefer not to disable the standby mode for the display as I like it to shut off after periods of inactivity and not stay on the screensaver - this would mean I'd have to turn the power off on the front of the monitor and I always thought standby mode was better for a monitor than turning the power off and on all the time. My monitor is a Samsung 244T if that matters, although I suspect either the video card or something in Windows as the culprit.
To add, I noticed today it is being even stupider. While I was using it I clicked a link on the internet - screen went black, then refused to wake. The computer seemed like it must have entered a locked up state too, as the num lock wouldn't activate on the keyboard either. I had to reset the computer again to fix this. And there's something else odd it does after this occurs - all my stuff that was memorized in Internet Explorer is deleted. I have to re-login at all the websites I told it to remember. It's really starting to tick me off as I don't see how the video card can be essentially deleting cookies and whatnot from my web browser.
I presumed it might be a virus so I ran an extremely intensive virus scan with Avast, however it turned up no infected files. I do spyware checks all the time and the same goes for that too. I'm at a loss here, given the random cookie loss I'm getting this seems to be more than just the video card - something software based is causing a problem but I don't know what. I've installed nothing new since this started so there's nothing I could delete to attempt to revert the problem.
I have the exact same problem, I am using the R9 290 card,Sapphire Tri X version. I leave my computer idle for about 15 minutes and my monitor video signal is off and the monitor power button keeps on blinking, nothing happens if I move the mouse, press keys, etc. It is so random!
Also just like RavinRivie, I was browsing on Chrome one day and suddenly it turned off the video signal, pretty much the same symptoms as described.
I can not explain a loss of your browser info unless you did a hard reboot and corrupted the file on shutdown. What I have seen is that sort of a monitor problem. Mine turned out to be two blown caps in the power supply. I did have blinking light on monitor and had first ruled out the monitor as the problem, but replaced caps and problem went away. FWIW, mine is a samsung. I have a second dead one and had same problem with a sammy TV. Lousy caps.
NEC lcd 1912 monitor, XP Pro, Nvidia 7600 GT, similar monitor issues. No browser problems.
If comp idles for an hour or longer (roughly) the monitor won't come out of standby. Well, the first time it took 45 minutes. Then I kept playing with the On/Off button on the monitor. That took anywhere from a couple of minutes to 15 minutes to get a display up. Re-installed the vid drivers to no avail.
If the machine display goes to standby, it's set for 5 minutes, it _will_ snap back on OK, when I move the mouse. Again, in standby for, probably less 15 minutes, no issues. Longer than that and it's a problem. I'm guessing, but this monitor is almost 10 years old.
*** I did try a hard shut down and rebooted, still no display. So I'm guessing the monitor is getting long in the tooth.
**** Went into Power Options and set the monitor to Always On. Turned off the monitor manually and let the comp idle for 2 hours. When I turned the monitor back on, it went into flashing on/off button and then took a couple of clicks, but started right up.
***** I think the NEC is history. Tried another monitor I had sitting around for several years. Also gave up the ghost. (perfectly fine when I stored it.) Finally another I had functioned fine.