What's causing the eMac fuzzies?

[Buzz]

been swamped lately, not much sleep, etc., but reasonably new eMac has case of video fuzzies, that is more than just my own bleary eyes. confirmed by many others. video goes out of focus at a couple of resolutions (maybe more) for several minutes, times of fuzziness not consistent, then goes back into focus on its own. unit only a few months old, but had internal board of some sort replaced when only one week old, after "new computer smell" did not subside, and there was noticable hot spot on side of computer. been working well ever since, except fan has seemed slightly noisier since early childhood repair, until last couple of weeks when fuzzies appeared. any ideas? or take it into the shop? thanks,

Buzz
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