Last week I upgraded my MacBook Pro 13" mid 2012 RAM to 8 GB and I had random restarts. So I did a safe boot and everything was fine, two days later the same thing happened again and the again it was resolved on safe boot.
It happened again today after about 4 or 5 days and I had installed el Capitan beta yesterday on a 30 GB partion.
So today after this random restart problem. I started my Mac and pressed the option key and held it. Then selected my main hard disk to startup and then immediately after selection, I held the shift key so it would safe boot.
It booted just a bit more than half and hung and switched off.
I tried to go into recovery mode, but it booted to el Capitan recovery mode and the disk utility was not working.
If I try boot normally. It restarts 5 minutes after boot.
What should I do?
Is there any way I could change the startup disk without booting so I can boot into main hard disk recovery mode disk utility and maybe repair the disk or can someone help me troubleshoot?