My MacBook Pro is having some issues. It boots. But the graphics card doesn't get detected. You can remote in to it but looking at the Displays dialog in System Preferences, no graphics card is shown:
I took it in to see if it qualified for the free mobo replacement because it does have the qualifying NVidia chipset and the repair shop said they couldn't run the diagnostics tool on it because it wouldn't chime on boot. And therefore wouldn't boot from their external drive to run their diagnostics. I hadn't noticed that it wouldn't chime on boot.
But what does that mean? What does the chime tell you? Why would the machine not chime?