I'm not really sure what the problem could be, but since it only occurs when the computer has been sitting idol for a while, my guess would be that it might have something to do with the screen saver or sleep mode. Try changing those settings to off (or just delay them longer) and see if the problem still persists. I'm not really sure if that would be a software issue or a hardware issue, but it seems like a good place to start.
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I'm not really sure what the problem could be, but since it only occurs when the computer has been sitting idle for a while, my guess would be that it might have something to do with the screen saver or sleep mode. Try changing those settings to off (or just delay them longer) and see if the problem still persists. I'm not really sure if that would be a software issue or a hardware issue, but it seems like a good place to start.
I'm not really sure what the problem could be, but since it only occurs when the computer has been sitting idol for a while, my guess would be that it might have something to do with the screen saver or sleep mode. Try changing those settings to off (or just delay them longer) and see if the problem still persists. I'm not really sure if that would be a software issue or a hardware issue, but it seems like a good place to start.