Observation - iMac suffers hard crashes (does not accept input from mouse etc; sometimes repeats the last sound byte repeatedly; needs to have power button held in for 10 seconds to turn the machine off) at random times - sometimes when it is not directly being used ie in sleep/idle.
Theory - HDD inside Early 2009 iMac 24" is flaky, resulting in random system failures.
Proposed Diagnosis Method - Boot from external USB drive and test iMac to see if it crashes.
Method Note #1 - Use clone of existing internal drive to rule out software issues.
Method Note #2 - Use fresh instal if #1 still results in failures.
Is that method sound? Or will the iMac still “use / access” the internal drive, even if I do not tell the machine to access its data? Can the drive still cause issues simply because it will automatically mount?
Basically I am looking for a diagnosis without having to replace the hard drive… I thought this may save me some time / messing around inside the machine…