M17x R3 going in and out of Sleep Mode

Hey people,

My M17x R3 started acting up again.. First I had the dreaded Optimus problem with my 460M. Anyway, I am using the A08 modded BIOS (as advised here in the forums) and for some time now I was a happy customer.

For the past 2 months there has been a strange problem. As I'm working on my laptop, it will go into Sleep mode (sometimes even when I'm on Skype, so I may be not touching anything!). This switch-on/-off behavior is pretty random but it has become more frequent as of late.

There is some differentiation when it comes back up:
Scenario 1) After 5 - 10 seconds it will come back to the Windows logon screen. All my processes are still running.
Scenario 2) It will not come back up and I will have to hold the power button down for 5 seconds. Then it will wake back to the windows logon screen. The processes are still running.
Scenario 3) It will not come back even if I press the power button. I would have to unplug and plug it again and then it will restart from scratch.

I am trying to find a cause to this. I have tried running the computer with battery and A/C adapter, Battery Only, A/C adapter only and all of the 3 scenarios have happened in all 3 cases.

The only thing that I have found as a probable cause was in Windows Event Viewer.

In Event Viewer you get categories of possible errors/warnings/info. For some errors, the time completely matches the time when the laptop goes to Sleep.
So, in the center window with all types of errors, when I navigate to Information > Kernel-General (Event ID 1) I get errors of the type:

For the same error again in Information > Power-Troubleshooter (Event ID 1) I get the message that the machine recovered from sleep.

I see that this time-adjustment thing happens all the time, but sometimes it coincides with the behavior of my laptop and I wonder if it is the cause.

If your list of these messages in Information > Kernel-General is as big as mine (31 events in 3 months out of which 10 - 15 are the sleep mode ones) it would be good to know.
If you've heard of this before I would be glad to have some guidance. Thanks for all your help.

 

Sorry for the double post.

I have posted my problem on the Dell Community Forums as well. From the suggestions the rep made, I guess it can be a graphics card related problem. I have updated to the A12 BIOS as she suggested, but it happened again 2 days ago... I'm waiting for an answer from them. we'll see...