iMac 17" with vertical lines, replace screen the correct solution?

I have a iMac 17" 1.83 Core Duo with the well known vertical line problem. From what I understand they are caused by defective multiplexers in the screen itself.

Now I have a second iMac of the same series with a defective mainboard but good screen!

I could swap-out the screen from the other iMac with the vertical lines. But! I heard that the vertical lines where caused by a defect in the mainboard, so that they will come back very quickly. Is this true? Or can I save the system by replacing the screen?

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crwdns2931729:0crwdne2931729:0: Ndz 20, 2016

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Hook it up to an external monitor to isolate the issue. If you have a bad GPU the lines will be on the external. Let us know your results.

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That is what I did, so as I said the defect is in the Multiplexers of the screen. External has no lines, also other screen from other iMac has no lines after replacing the defective one.

But the question was: will the lines come back on the new screen because an undetected defect on this mainboard or powersupply.

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iMac Intel 17"

iMac 17" with vertical lines, replace screen the correct solution?

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