Turns on but no video is displayed, is it the graphics card?
Okay, my question today regards my older 2008 Mac Pro 2x2.8 QC Mac Pro. It has a 7300GT Graphics card in it right now. When I went to restart it after installing Lion last night it sounded like it was booting up and chimes but never displayed anything on the screen. When it is fully booted and I press random keys it makes the "bonk" sound when it can't do something. I tested the display and connectors with my newer Mac Pro and the display worked fine. Has anyone had this problem before and could it be a faulty graphics card. I would take the card out of my newer on but it is running as a server and it can't be turned off. Any help would be appreciated, Thanks!
Try a safe (shift) boot - there could be an extension conflict, or the install may not yet be complete, or corrupt.
If the safe boot doesn't work, yet the monitor does with a different device, I would agree the likely fault is the graphics card. Replacing or substituting the card is the only sure way to identify or eliminate it.
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