New Inspiron 15 7000 Gaming (7567) HDMI Out questions

I have a new Dell Laptop, the "New Inspiron 15 7000 Gaming", specifically the 7567 variant.  Before I start, just to let you know my technical experience, I work in the IT field, and have extensive knowledge of building computers, how drivers work, etc, just to give you an idea of my experience. 

I have a couple of problems with video output on the HDMI channel.  The problems I'm having are when I use the HDMI port with my TV.  My TV is a Vizio M422i-B1, and using up-to-date cabling.  I don't have any problems using the laptop with it's built-in panel, and this laptop works perfectly when used in that way. I though will be using this laptop primarily attached to an HDMI port to my TV, and I'd like to know if changes could be made somewhere on the Laptop in a BIOS or utility I'm missing, or if I may have come up with some feature updates in future BIOS revisions - if possible.

The first problem is there is no video signal sent out on the HDMI port during boot and in the BIOS screens. When Windows starts, video signal is sent and everything appears to be working normally.  This is a problem if I want to access the BIOS, or boot to Safe Mode, or do something in the preboot environment such as booting from a USB drive. I don't see anything in the BIOS or anywhere else that would allow me to enable sending video through the HDMI port in this boot phase.

This leads me to the other problem I'm having.  After Windows starts, the desktop environment stutters, or appears to have noticeable lag, constantly throughout operation.  In addition, the Intel HD Graphics shortcut in the right-click menu disappears. It appears that I cannot configure the Intel Graphics settings while the lid is shut and attached to HDMI. Now here's the weird bit. When I open the lid while still attached to HDMI, the Intel Graphics options DO appear in the right-click menu, and my desktop environment is fluid, stutter-free, and works like it should.  But, when I close the lid again, the Intel settings disappear, and performance is very sluggish.  The only way I've managed to get a fluid experience on the desktop again is to remove the Intel Graphics drivers, or leave the lid open. I don't want to do either of these things, as the Intel graphics drivers need to be installed so I get correct performance when using the laptop by itself, and I don't want to leave the lid open while using it attached to the TV.

Here's a list of the things I've tried. 

• Uninstalled both Intel and Nvidia graphics drivers, rebooted. Installed Dell drivers from the Dell website. Same results, stuttery, laggy desktop.  (Install order was Intel Graphics, reboot, Install Nvidia Graphics, reboot.)
• Uninstalled both Intel and Nvidia graphics drivers and used drivers direct from Intel and Nvidia. Same results. 
• Tried different cabling with no change. Have ordered new cabling that supports the latest HDMI standard, not sure if this will make any difference at all.
• Set computer power profile to Maximum Performance.
• Set in Nvidia driver prefrences to exclusively use the Nvidia graphics processor. No change. 
• There are no options in the Intel settings for HDMI/preferred processor that I could see. 
• Uninstalled Intel Graphics drivers and rebooted - had fluid desktop the whole time I had the basic VGA driver installed for the Intel Graphics portion of the hardware. Re-installing the Intel Graphics driver results in stuttery, laggy performance again. 

When the lid is shut, which GPU handles the video signal? Is there a possible conflict at the hardware level that might be able to be fixed? 

I will say though, that gaming performance is incredible on this laptop though. Every game that I've played on it so far has exceeded my expectations. Gaming on both the built-in panel and through HDMI on my TV works perfectly. Even though that's what I'll be using this laptop for the most, I would like to know if there is anything I can do to improve the performance in Windows while attached to HDMI. I know this laptop is capable of providing a smooth, lag free experience in Windows itself.