Computer wakes up to a black screen in Ubuntu 12.04 dual booted with Linuxmint 14 Cinnamon on separate hdd

I have experienced this issue many times with windows let alone ubuntu, Mint, Debian and the like. I tend not to use suspend for this reason, but it has worked on Ubuntu 12.04 and earlier for me, but is highly dependent on your motherboard and video card.

The first thing you must do which you have done is make sure suspend to RAM (S3) is enabled in the motherboard BIOS. Following on from that in the motherboard BIOS ensure that hard drive spindown is disabled and DPMS is enabled (also try disabling this if it is enabled, that is if the option is in the BIOS).

Also ensure if the option is available, set the 'Plug 'n play operating system installed' set to YES. Recently on Ubuntu I stopped using the ATI and Nvidia drivers and use the Ubuntu one as I found them buggy, booting to a black screen, no desktop and constant crashing. It helps some times to list out the hardware ie motherboard, RAM, Power supply, video card as it can give an idea of a buggy ACPI setup in a BIOS which can be resolved with a BIOS update or slightly incompatible components.