Studio XPS 8100, delayed video output

It is a known issue with certain XPS models that preboot test or POST may take up to 45 sec before you see Dell logo.  The delay has been attributed to USB devices including Dell 19-in-1 media card reader, etc.  For some reason firmware test of these usb devices takes time than usual.  It is not a fundamental flaw but can be irritating.  Disconnect as many USB devices as possible from XPS and see if that helps.

Thank you for your reply.  The only two USB devices currently plugged into the system are the keyboard and mouse.  I've unplugged the mouse and replaced the keyboard (if I simply unplug the keyboard, the system will not boot) but the delayed video output still occurs.

I also tried the on-board DVI and found that it did not work at all.  I found out from another post, however, that for this system that is "normal" if it came with an i7 processor, which it did.

Also, you stated that "it may take up to 45 sec before you see the Dell logo".  When the video finally appears, that portion of the boot sequence has already occurred.  The first thing that I see is the Windows Welcome screen, followed by the desktop.

it is not normal to have no video from on board DVI.  I have never heard of i7 1st gen lynnfield cpu for lga1156 do that. but anyway you are getting video from quadro albeit much delayed and no way for you to enter BIOS.

if you have a media reader on front panel, it is also an USB device that you need to disconnect its cable connection to motherboard (I think I mentioned the Dell card reader being one culprit) to see if that helps the video delay.  However the delay I mentioned before does not stop you from seeing Dell logo and pressing F2 to enter bios.

I suggest you power it off. remove cmos battery for a few hours. reset cmos jumper on board.  then boot again to see if it changes anything.  it may be a cmos glitch that needs to be cleared.

Onboard video ports not working probably has nothing to do with the CPU that's installed, unless -of course- that specific CPU doesn't have onboard video.

Onboard video ports are typically disabled when an add-in video card is installed. If you want to use one of the onboard video ports, you have to physically remove the add-in card first. Just moving the video cable from the add-in card to an onboard port won't work, as you've already found out.

BTW: You didn't say what video port you're using on the add-in video card. If it's not the same (eg DVI) as you tried with onboard video, do you have to tell the monitor which port to use?

Some monitors are dumb and have to be told which port is connected. If the monitor has an On-Screen Display (OSD) that's opened by pressing a button(s) on the monitor itself, open the OSD and make sure it's set correctly for the port you intend to use, eg DVI with onboard video, after the add-in card is removed...

@RoHe is correct.   all the LGA1156 quad-core parts were GPU-less.  so both i5 and i7 lynnfield cpu do not have integrated graphics.

I did not know that.

@Kenobi-Wan  thank you for explaining to us all the diagnostic steps you took so far.  I understand it is frustrating and time consuming to trouble shoot.  I think you mentioned you wanted to enter bios but you can not now.  here is a way to enter bios through windows 10.  https://www.faqforge.com/windows/windows-10/how-to-access-the-bios-in-windows-10-pc/

another test to try is change the discrete video card from quadro to a very simple video card if you have one.

Thank you folks for your attempts to help.

The first thing I tried to get around this issue was removing the add-on video card and using the on-board (both of which were DVI) but when I tried to boot the PC without the add-on card, all that resulted was an orange power light an a 6-Beep error code.  Searching online using this information took me to the following thread:

https://www.dell.com/community/Desktops-General-Read-Only/Studio-XPS-8100-On-board-Graphics/td-p/4512547

I tried removing the battery earlier today as redxps630 suggested, and ended up with a system that turned on but did absolutely nothing.  My guess is it realized that the BIOS had been changed and was waiting for some kind of input from the keyboard.  Since I couldn't see what was happening I just started pressing "common" keys and through trial and error found that the system would continue booting if I pressed the F1 key.  I did not, however, also move the CLR_CMOS jumper so I tried it all again and waited for two hours.  Again, no boot until I pressed the F1 key, then approximately 40 sec. later, I had the Windows Welcome screen and finally the desktop.

That would be a great solution... Unfortunately, the PC still has Windows 7 on it.  That's the reason I wanted to boot the system from a flash drive.  I'm wanting to put Windows 10 on it and like all of the other PC's I done over the last 4 months, I always try to do a "clean" OS install by booting from my Windows 10 Install flash drive and removing / recreating the hard drive partition to virtually guarantee that nothing from the previous OS remains.

If nothing else, I guess I could do the upgrade to Windows 10 with the Windows 7 OS still in place and then use the method you referenced above to get into the BIOS settings.

That is how I install Win 10 too. two suggestions 

remove hdd from XPS 8100 and clean install Win 10 on it in another PC if you have one. when you are done transplant it back into 8100. let Win10 auto-adjust to new hardware.  I have done this way many times. In my experience Win10 much more robust than Win7 and almost never crashes during this.

or burn a Win 10 DVD to see if 8100 can let you boot from it instead of hdd (of course we do not know your boot device priority).

back to your original issue of no POST video.  someone reported exactly the same issue. https://www.dell.com/community/Desktops-General-Read-Only/No-video-in-bios-startup/td-p/4151174/page/2
suggested fixes: install the latest Chipset and Video drivers from the Dell Driver Downloads.  if using a DVI to VGA adapter, removing that adapter and connecting to a DVI monitor.

The solution is OEM system builder dvd to F12 boot from.

You need to make sure your region setting   1 for usa is correct for the dvd before trying it.

Then press enter when it says press any key to boot from dvd.

https://www.newegg.com/microsoft-windows-10-pro-64-bit-reinstall-recovery-disc-only-no-license-key-included/p/N82E16832350238

You can use the WIN7 coa key to activate online after using generic key to instalL

VK7JG-NPHTM-C97JM-9MPGT-3V66T (Windows 10 Prol)
YTMG3-N6DKC-DKB77-7M9GH-8HVX7 (Windows 10 Home - multi language)
BT79Q-G7N6G-PGBYW-4YWX6-6F4BT (Windows 10 Home - single language)

How do you connect your NVIDIA Quadro 600 to monitor? DVI to DVI?

do you have another computer running Win 10 currently? If yes can you borrow the hdd from that computer and try to enter bios of 8100 through Win 10?

I used the Windows Media Creation tool to download an ISO of the Windows 10 install and ImgBurn to create my own install DVD but to no avail.  I even unplugged the hard drive so that the system would have "no other choice" than to boot from the optical drive.  I have to wonder if the BIOS is set to boot ONLY from the hard drive?  As I mentioned before, pressing F2 or F12 blindly on startup just stops the boot altogether so if the optical drive isn't already in the boot order lineup I'm stuck.

I also updated all of the system drivers and the BIOS as suggested by redxps630 but alas the results are still the same.

Yes, DVI to DVI.

I can try the HD from another PC I updated recently.  It's worth a shot.  If things go sideways, I can always re-do that one again.  I'll let you know what happens.