Dual Moniter Vista Flickering


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I'm trying to run Dual Monitor's off my Acer Aspire 6920 laptop. It's specs are 2.5 pentiuim core 2 duo, Nvidia GeForce 9500m GS, and 4 gb ram, and I'm running Vista Ultimate. I'm trying to hook a VeiwSonic 19" widescreen monitor to it. Everytime that i do, both screens flicker as if the signal is being lost and found constantly, until i unplug the 2nd monitor. I can use the VeiwSonic as the main monitor and have my laptop screen off without problems. Sorry for the length, but any help would be greatly appreciated.

~thanks - eric

Edited by Eric
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is this DVI or VGA connection?

Sounds like HDCP issue but I can't see a reason why.

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then its a HDCP issue. you are limited by the resolution size you can send analog now. and both screens add up to greater than your size.

if you can use DVI and your monitor is HDCP compliant it will work..

Don't you like being treated like a thief.

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then its a HDCP issue. you are limited by the resolution size you can send analog now. and both screens add up to greater than your size.

Eh? Every computer I've used has been happy to push as many pixels over VGA as the hardware could manage.

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not anymore, I just ran into with an install, where the sharp monitors were not HDCP compliment, and the Other was. when using only one monitor the screens were fine. when using two they would flicker. Since this is a Laptop the first monitor (the Laptop one ) is compliant and so Vista is running in Protected mode. so when the other come up VGA it will at a high resolution HDCP kicks in. Its like how Macrovision used to scrambel colors, but it causes you monitors to flick on and off.

we fixed it by finding nvideo cards with the same chip but 6 onths oler, as they did not have the HDCP chip on the board. The monitors worked 100%.

for the newer systems that will not take AGP we used a Gefen DVI Detective to capture the HDCP information from a compliant monitor and place it on the second. VGA is not HDCP compliant.

Trust me this sounds dumb to anyone who has don computers for any given time. and it took us and 3 professional AV engineers to diagnose this correctly.

the only other thing it would be is a bad frequency, but you never see that with VGA, the signal is there or its not, its analog. but with DVI over a long stretch this is common. this is why I asked if it was DVI or not.

If the monitor has DVI you can use but your laptop does not, iogear make a USB DVI adapter This works well at 1600x1200

just a note we are also having this problem with Workstations and KVM's. the DVI inspector is the only way we have fixed that.

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not anymore, I just ran into with an install, where the sharp monitors were not HDCP compliment, and the Other was. when using only one monitor the screens were fine. when using two they would flicker. Since this is a Laptop the first monitor (the Laptop one ) is compliant and so Vista is running in Protected mode. so when the other come up VGA it will at a high resolution HDCP kicks in.

Shouldn't that only happen when you're viewing protected content that forbids VGA output? I'm looking over one of the Vista content protection whitepapers and it seems clear that they wanted VGA to work. [Edit: By "work" I mean "not be disabled". Microsoft seemed to favor degrading the content.]

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that is why it took so long ot diagnose the issue, we thought the same thing. I was Working With Dimensional Communications who did all of Microsoft's AV testing at the MS headquarters for VISTA. It was one of their engineers who alerted us that this was an issue. We were doing zero "protected Content" just the desktop..

VGA is not disabled, its using it with DVI, I can make it work at 1280x1024 but once I go higher I run into the same problem, if I havea DVI connections..

There is a chance I am wrong as always, but flashing screens are one of two issues, HDCP or a freq mismatch. and a direct connections to the monitor should not ever have a Freq mismatch.

So there is the chance the poster has a bad monitor, or bad cable. but since both monitors are flashing , I would say HDCP.

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Bizarre. The first thing I thought of was that it might be a hardware or driver defect. I have a notebook that has a stroke when I try to drive a high-resolution display (an HDTV, specifically) on VGA. The built-in display works fine but the second display paints at about 5 Hz (software paints, I mean; refresh rate is fine, AFIACT). There's massive artifacting, too, but I don't know if that's the notebook or the TV's upscaling. I would say it was just beyond the IGP's capabilities but it's supposed to be a supported configuration and I would expect overloaded hardware would affect both displays similarly.

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