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The computer beeps 3 times and nothing else happens. Could it be that I didn’t install the power supply connecter correctly or something else. Don’t know what to do.
The 3 beeps is telling you the RAM failed POST About Mac startup tones Did you maker sure to fullyseat the SO-DIMM’s and make sure the latches are latched? Are you sure you are using the correct RAM for the system. Your system is only able to support 16 GB of RAM.