External monitor static when waking from sleep

I'm running two monitors with a 2010 MacPro, and recently started experiencing static on my main monitor. After stripping down the system to its most basic setup (usually a good idea when there's trouble), I realized that the problem was caused by the proximity of the 'converter box' that is part of the power supply cable of the second monitor (an old Viewsonic), to the display cable of my main monitor. I moved the converter box away from the display cable and the static vanished.

The converter box I speak of is connected by a thin wire to its monitor, and a standard computer power cord plugs into the other end. This is the same two-part design as the power cords for all of the scanners I've owned. Maybe the converter box of a scanner power cord that's too close to a laptop would produce static on the laptop's screen.

Hope this helps,

Greg

The static came back and I finally realized that my UPS battery backup was failing, when I took it out of the loop the static went away. Apparently there is another state that exists in those batteries, a state between 'good' and 'non-functional'. Clearly, the static messing up my monitor was from The Twilight Zone.

maximeauger wrote:

To everyone experiencing the frustrating "static on display when resuming from sleep", I think I finally got the solution to resolve the problem. Since the most recent versions of OSX are using "TV resolution" to configure digital displays (such as 1080p, 720p...) I thought maybe my mac was trying to "talk" with my displays in a "TV language" so I went in my SyncMaster's display setup and changed a few settings to fix the "miscommunication" between my mac and the displays. Surprise! After many months of frustration, it finally fixed the problem!

Here's what I changed in the SyncMaster's setup menu:

Under "SIZE & POSITION" menu, go to "Image Size" and set to "Screen Fit"

Under "SETUP & RESET" menu (down on the second page with my model), go to "Auto Source" and set to "Manual"

Finally,still under the same "SETUP & RESET" menu page, go to "PC/AV Mode" and set to "AV"

Bingo! Now when the computer wakes up from sleep, the screens are going back on like a charm!

Hope this will help people who had the same issue using MacPro with Samsung SyncMaster displays, worked for me anyways!...

Cheers!

I think you're onto something with the SyncMaster settings. I changed mine on a PX2370 monitor last night and haven't had the static since. Fingers crossed it's gone for good.

Thanks so much for sharing this.

FWIW I just stumbled across this issue on my Macbook as well, but it was green static. The difference this time was that I had plugged my iphone into the USB port directly next to the display adapter, with the iphone also directly next to the computer. It seems that either the USB being plugged in there, or the phone getting powered on were giving RF interference? Because the second I unplugged it, the problem went away. Switched to the USB port on the other side and all is good. I know this isn't what many of you are dealing with but posting this for anyone else who might google the same issue.

zeugmatis, I think you're on to something as well here. I had the green static issue in an external display for the first time yesterday with an early 2011 MacBook Pro i7 which is hooked up to a PC display via the minidisplay to dvi adapter.

It wasn't too big a deal, I just unplugged the adapter and plugged it back in again and it was fixed. But, I think it was also from having a couple of devices in the USB ports right next to it that may have triggered it. Perhaps my iPod being plugged in had something to do with it.

If it happens again, I'll report back here. I'm glad to see others are reporting the same thing, I came here to check it out and see if it meant my graphics card or something is failing, but it sounds like from reading the posts here that it's just a weird glitch?

Hello Everyone,

Needless to say, I find myself in a predicament as described in the thread. Contrary to what some people may believe, it is not "trivial", because owning a Mac is, amongst other benefits, all about the device simply working whenever you need it to - no tweaking. Repowering the monitor every time you wake your Mac is hardly conducive to attaining this goal.

Complaining aside, I have possibly traced the problem to the characteristics or quality of the adapter used to connect the Mac to an external display. It may stem from the fact that adapter is a "passive" one and not an "active" version (Thunderbolt > two HDMIs) such as the one required to connect six external displays to a Mac Pro. It also may be so that many people feel disenchanted by the considerable price Apple puts on the adapters and inclined to search for less pricy alternatives. It would be very helpful to hear from fellow troubled users and learn what kind of adapters they are using.

The difficulties are almost certainly software-related, however, knowing what kind of hardware brought on the unusual behaviour could prove useful too.

I have exactly the same problem with a 13" Mid 2012 Macbook Pro running 10.9.5 and connecting by Thunderbolt to HDMI to a AOC monitor. The original cable was a cheap 2 meter one from Ebay. Cheapest I could find. After I had the problem for a long time I bought a slightly more expensive cable to see if it was the cable, the problem still persists. I have had the macbook in for servicing with Apple twice as I'm experiencing a problem where I can't wake my macbook from sleep but when it returns (temporarily fixed) the static issue is still there. I don't know if these two problems are connected but the service engineer told me that something I am plugging in is damaging the laptop and causing the wake up issues. He suggested it was due to a cheap iPhone cable but I imagine it is the something to do with the thunderbolt display connection. Anyone else having wake up issues?