I realize this is an old post, but I'm having the same exact issue. After laying down my windows 7 image on a E6520 or M4600 laptop and sysprep is run, Optimus is disabled in bios, even though it was checked prior to sysprep being run. I have PersistAllDevices enabled in my sysprep answer file, but it made no difference.

If you aren't doing any BIOS modification during your build process, then the only possible answer is the order in which the display drivers are being applied.  I can't think of anything else that could be affecting a BIOS setting without directly interacting with it.

I am also facing the same issue for a long time and already gave up on this, we enable the Optimus once the imaging is done and have to install the drivers manually.

Warren, what do you mean by order? I deploy the images using Altiris (Symantec) and I don't think there is an option to change the order.

My point is if we are enabling the Optimus option in BIOS and then installing both the Intel and nVidia drivers and then capturing the image. This image is then applied to a same model of computer and the option is disabled automatically from BIOS. I haven't tried Dell support as I know they won't be able to help.

GeekF,

The Nvidia documentation specifices that the Intel Driver should be installed first before the Nvidia driver.  With many OS deployment tools (Altiris, Microsoft) that is not an option.  I was just adding that as a datapoint for the discussion.

I would encourage you to give Dell Support another try as their formal support process is always the best way to ensure that an issue is addressed.  

We are working on a method to get conversations in this community transferred to the formal support teams when necessary.  In the interim, use the contact information below to open a ticket.

support.dell.com/.../contact_technical_support

Dear Warren,

Thank you for your reply.

Yes, I've seen the video card driver behavior. If Optimus is enabled and  you try to install nVidia drivers, it will ask you to install the Intel Drivers first. Without Intel, you cannot install nVdia drivers.

I'll try contacting Dell Technical support and will update this post with the result.