Since you've been through so much, I assume it must be a configuration issue (or maybe a conflict). Before we look into that, there are a few things to try:
All troubleshooting should start by inspecting Microsoft's Event Logs. In the case of Windows 7, begin by clicking Start, then type event. Once you launch 'View Event Logs, review the Critical Errors in the last 24 hours. Follow-up by looking in the Windows Logs and filtering the System Log for 'Kernel-Power' entries. Interesting items would include 'The last sleep transition was unsuccessful', or 'The system is entering sleep'.
I am willing to bet that 60% of all Sleep and Hibernate problems are due to inappropriate settings in the Power Options (Control Panel, Hardware and Sound). For example, if you see no Hibernate option on the Shutdown menu, then check whether 'Allow hybrid sleep' is set to 'on'. You could start this line of troubleshooting by pressing the Windows key +x on a laptop, or Start Search, powercfg.cpl on a desktop. See screen shot of Allow hybrid sleepCertified for Windows 7 logo
Does the Bios Support Sleep Mode?
Provided the computer has the 'Certified for Windows 7' all the power management features are guaranteed to work. It's just up to you to configure Sleep or Hybrid Sleep, or else complain to the supplier / manufacturer.
To check your computer's Bios you need to interrupt the initial boot phase. For this inspection, seek a special key, it maybe F2, or maybe spacebar, it could even be the delete key. If all else fails read the boot screen! Once you have intercepted the bios boot, just carefully examine any options which could enable / disable Sleep. What you are looking for is settings such as,
S3 - Suspend to RAM (Sleep)
S4 Suspend to Disk (Hibernate)
Idea: See if there any updates for your BIOS. If so a later version may cure your sleep problems.
How to Stop Your Computer from Going to Sleep (or to see if it has been told to not sleep)
1) Navigate to the 'Power Options' (Start Search powercfg.cpl)
or see above.
2) Select your power plan.
3) Click: Change plan settings.
4) Crucial Links:
a) Change advanced powers settings.
b) Change settings that are currently unavailable.
5) Research the myriad of settings, in particular: 'Sleep'
6) Expand: 'Sleep after'. If it's a laptop check both the 'Plugged in' and the 'On Battery' settings.
7) Choose: 'Never' to prevent your computer going into sleep mode.
Windows 7 Hibernate Problem: Windows 7 Hybrid Sleep (No Hibernate Option)
There are at least two different types of hibernation problems. One problem is that your computer is not waking up properly. Alternatively your problem is there is no Hibernate option on the Windows 7 Shut Down menu. In both cases check the 'Allow hybrid sleep' setting.
1) For any hibernation problems the easiest solution is to set 'Allow hybrid sleep' to: 'Off'.
By design, hybrid incorporates both Sleep and Hibernate, thus you only see Sleep on the Shutdown menu. Also, by default, desktops are set to 'Allow hybrid sleep :On'.
Trap: Before you can change any of the Balanced settings, first you must click on Change settings that are currently unavailable.
2) Another problem with hibernation is caused because Windows 7 does not have enough free disk space for hiberfil.sys. My machine needed 4 GB, the size of my RAM.
3) An over-active Disk Cleanup program may cause the Hibernate option to disappear. If Hibernate does not appear on the Shutdown menu, then open a command prompt and check with:
If this was your problem, for future reference you could remove the tick next to 'Hibernation File Cleaner' in the Disk Cleanup settings.
Next turn on Hibernate with:
Powercfg -h on
3a) Check for errors with:
Incidentally, Powercfg -energy gave me errors and warnings - even when the computer awoke from sleep gracefully. However, the point is that the information in the html report may point you to which devices need further investigation and driver updates.