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42LG60 Thinks my VGA input is an HDMI input?


Standard Member
***SOLVED! See my next post

I've got a 42LG60 that I'd like to use (among other things) to watch movies from my laptop, connected via an SVGA cable. I'm having a serious issue with random flickering however. Whenever my primary laptop (Running Vista) is connected to the TV via the SVGA cable, the TV tends to flicker randomly as though the computer is constanty trying to auto-set its resolution/output to optimize the picture for the TV. In fact, when I try to set the TV as an extension of the desktop (as opposed to a clone image) it does so, flickers like crazy for 3-7 seconds, and then changes it back to a clone image (and this isn't a result of "Your settings have been changed, please accept these settings or they will be changed back in 15 seconds"). I suspect it's a plug and play setting that I need to disable, but I've looked and I don't know where or how to do that with Vista.

I tried hooking the TV up to two other computers though, one laptop and one desktop both running windows XP and it worked flawlessly. I tried multiple resolutions, refresh rates, etc etc, and it worked each and every time on these computers. Trying identical settings with the Vista laptop and I continue to get the flickering/flashing. One thing I'd like to stress is that the flickering is random. If I start a movie it might play fine for 5 minutes, then flicker randomly every few seconds for a minute, then be fine for a minute and then flicker once, then calm down, etc etc.

One thing I noticed though, was that when connected with the XP computers I could not set the resolution of the TV in the picture settings. That is to say, the TV was allowing the computer to control the TV resolution and acting like a monitor. When the vista computer is connected (in the exact same manner and SVGA cable) I can edit the TV's display resolution, which I think is a setting that's typically adjustable when connected to a computer via the HDMI input.

Any thoughts on what this might be? I've got access to one other Vista computer which I hope to try, and worst comes to worst I suppose I'll just run the TV off an XP laptop - though this vista one is considerably faster :(
Last edited:


Standard Member
If anyone has the same problem or is curious, I finally solved the problem. Turns out it was stupid vista.... Man I hate this OS

Here's the link where I found the solution, as well as a copy & paste should the link ever die.

Vista external monitor flash and flicker problem solved | AuctioneerTech

Vista external monitor flash and flicker problem solved

One of the first pieces of auction technology adopted by an auctioneer augmenting his business processes is a projection system. I was at an auction in Denton, Texas, where there were more than 30 large plasma and LCD TVs - most to be sold that day - showing the same display of the item currently selling. The ability to make the crowd comfortable and more informed by providing chairs and a completely pre-lotted inventory is generating much greater returns for auctioneers who have it.

Whatever the display method, be it projection or TV or monitor, there is a computer driving it, usually with a cable connected from the VGA, or monitor, output to a VGA splitter. That splitter then amplifies the signal and offers two, four or more VGA outputs to run cables to all the display units.

One of the problems we’ve faced is an issue with Vista notebooks. We’ve noticed it with both ATI and NVidia graphics sets, so it doesn’t seem to be manufacturer specific. All of a sudden, seemingly without warning, the display will flicker or flash, almost as if the computer is re-detecting the external display. Most times, the flash is accompanied by the sound that Windows plays when it detects new hardware, confirming that this process is indeed what is occuring. This detection, refresh and re-detection can go on, sometimes in a continuous loop, until you unplug the external display’s cable from your notebook.

We’ve historically simply made sure that the computers we’ve used for digital projection were running Windows XP, but as this practice becomes an increasing security risk and as it becomes harder to find new laptops with XP, it’s simply both unwise and unpractical.

My recent purchase of an ATI-based notebook which exhibited the problem frequently both confirmed that the problem wasn’t specific to NVidia and made me determined to find the solution. I came across this thread in the vistax64 forums and the fix has been working great for me for the last 24 hours.

As it turns out, the problem in notebooks seems to be caused by a process called the Microsoft Transient Multi-Monitor Manager that is supposed to detect when you plug-in or unplug an external display. As it turns out, it is a little too sensitive, causing the system to think you’ve done this action when sometimes you haven’t. This errant re-detection causes the system to refresh its display settings which causes the flicker and flash. Here’s how to shut down the TMM.

1. Run task scheduler by clicking start button and then typing “task scheduler”
2. Browse to Task Scheduler Library > Microsoft > Windows > MobilePC
3. Click TMM in the list at the top-center
4. On the right pane click disable

After you reboot you should notice no more unexpected flashing. The solution, however, does have the side effect of requiring you to tell windows any time you connect an external monitor, but that’s easy and a small price to pay for the comfort of knowing that your auction display won’t start flickering on and off when you’re in the middle of an auction.

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