Brett Archibald

Q: I have weird pixelly artefacts showing on my screen...

Can anyone tell me what is going on with my iMac?

 

I have weird pixelly artefacts showing on my screen.

The attached picture shows a particularly bad portion of a screen grab of this, taken in Safari whilst browsing a website.

The lines and blocks flicker like crazy. They're not moving around, and where they appear, they stay flickering in that spot – BUT if I move the browser window, then weirdly the flickering lines and blocks follow along with the window.

If I flip to a different application, then the flickering lines and blocks might move to a different location, or they might disappear altogether, or there might be more of them or there might be less of them. It's all very random.

Also, as you can see, for some reason I have lines appearing over a dark section where there is an image, and I have blocks appearing over a light section where there is no image.

It can be seen in any application, be it Safari, the Finder, Photoshop, anything...

Some days it's a little bit, some days it's a crazy amount. It usually disappears totally after a reboot, but then after restarting, the flickering lines and blocks gradually appear over time.

 

Any help appreciated. Thanks.

 

 

Running 10.9.3 on a 2.7GHz i5 iMac.

 

screen-artefacts.png

iMac (27-inch Mid 2011), OS X Mavericks (10.9.3), 2 GB RAM

Posted on Jan 22, 2015 8:20 AM

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