Old iMac won't boot. Tried to boot Linux via USB, but got this awesome effect. I suspect a failing GPU. : r/techsupportgore
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Got a iMac Late 2009 model A1311 for a very good price, made a bootable USB drive for El Capitan and this shows up. any ideas? All help is appreciated : r/osx
Apple iMac (Winter 2009) review: Apple iMac (Winter 2009) - CNET
Adding USB3.0 to late 2009 iMac (11,1) | MacRumors Forums
Replacing an iMac Hard Drive with an SSD | All Apple All Day