I do have one idea.  Make sure fast boot is enabled in Win10.  Control Panel > Power Options > Choose what the power button does > Show options currently unavailable > Check box for "Turn on fast startup."

If the box is already checked, one can uncheck it and see the response.

https://www.google.com/amp/s/www.howtogeek.com/243901/the-pros-and-cons-of-windows-10s-fast-startup-mode/amp/ 

One possibility is the system isn't recognizing the NVMe PCIe 1Tb SSD right away.  But that I don't have any ideas for.

Did any recent updates slow it down?

Did you ever figure this out?

I have a similar experience

TIA

Hello, i have the same problem, is there any solution?

Going to intrude. Giving the same happens on a later series equivalent, I think it's running self tests before the logo, by design.

And I doubt that those can be bypassed. Moreover it's just some seconds, is nothing so major... if you had a more server oriented setup or more cards doing post messages ( raid config , press xxx to enter setup  //  press xxx for remote boot // etc ), what would you do ?

For me these times are more than reasonable ( but it would be nice to have the option to see notifications about the tests being done )... I would like to see you try to boot up an as/400 and wait 20 minutes while all is checked and certified bit by bit 

5820

boot init is very slow. I see no option there. They just have not implemented the bios fast init, like in home systems. Unfortunately, it is common for workstations. I have an old ASUS x79 Deluxe based LGA 2011 workstation, and yes, it boots 2 times faster. But it is i7 without IPMI, and DRAM ECC.

I have the same issue. My average boot time on Windows 10 is 30-35 seconds, with as less as possible programs enabled on Start-up. What bothers me the most is that te screen is black, and as mazzinia mentioned, I guess there should be at least any warning  or message that tests are being performed.

I have the same problem and as I can see here answers are not related to your questions. The problem is about bios. I have T5810, and I had a T3500 which had twice faster boot even it has very old hardware.
I have shortened a bit screen post time and waiting on the DELL logo.
Try those in the bios menu (access via F2
Turn off the keyboard and other error check options
Remove unrelated drives from the boot menu (like Cd/Disket/LAN, leave only hdd with OS in it)
If you have PCIe GPU, chose manually which gen support from the performance menu
Update Bios (didn't work for me)
As I mentioned this is a Bios issue, in those models it might be more process going on when it is booting up. Of course, NVME hdd shortens booting time but doesn't affect pre os boot time.
Those tips are not only specific Dell workstation model, it can be applied to any model even the newest ones.
Hope it will help.

This is a rant, ignore it if you want because I don't have a solution to offer at this time, but I'm frustrated with the boot up time on my Dell 7910.

I have been facing the same issue ever since I bought a Dell 7910 workstation with 64GB RAM.  Perplexed about this, because I also have an HP Z600 workstation with 48GB RAM and that booted like a PC would - quick I mean.  Both have dual Xeon, if anything, HPZ600 has older hardware but boots up significantly quicker compared to Dell.  These are 'workstations' not servers, so I am quite intrigued by almost every discussion that I found in a quick search on the internet saying this is okay and to just live with it!  Well, that does not explain why a different model in the similar class of powerful workstations would boot up what feels like 'normal' and this Dell would just test your patience at every boot.  I even checked by moving the same SSDs between the two systems, and moving the same  secondary graphics card between the two systems: an NVidia 1050Ti as well.  The primary graphics card on both systems is a key difference, though I wouldn't expect an AMD R290 on Dell causing it to boot significantly slower.  Of course, another key difference is HPZ600 not supporting TPM 2.0 (it has TPM 1.2) and not supporting UEFI, but I also tested with Dell 7910 in MBR mode boot up - still painfully slow.

One buys these workstations for speed and no, having used these workstations for several years, unlike some posts on the internet suggesting these powerful workstations are usually meant to be kept switched on 24x7, I beg to differ - that's not my usage pattern (to keep these on 24x7 unless updating etc.) and it certainly can't be a viable pattern in these days of energy conservation and climate change, whatever.

I already had a specific slot marked as primary video card slot instead of 'auto', in the hope the boot up process can be a bit quicker instead of detecting and deciding which one to make primary.  I had the other 'optimisations' referred in the post above as well, but I don't think they helped much in my case.

I am surprised why Dell wouldn't do anything about it because I would personally think they are in competition with vendors like HP for such workstations and the boot up time differences between the two are significant (it matters from perception point of view - don't have to sit twiddling my thumbs for a long time with the HP).

Am not affiliated to HP, not affiliated to Dell, I don't care how each of these companies commercialy performs etc.  Am just an end user of the workstaitons and want my Dell workstation to boot up quicker, just can't figure out how despite the latest BIOS from 2020, SSDs, etc. - boot up time matters too, not just perf after the system having booted up fully.  None of my SSDs are configured in RAID, though both systems support RAID.  The perceived 'slowness' in boot up is not due to SSDs anyway, once they get going loading Windows, it proceeds normally from there, the 'slowness' is before that, in POST and showing the boot manager.  There is no option to switch fastboot to 'minimal from 'thorough' - the option does not exist for me in the POST configuration section within the BIOS Setup.

Workstations and servers with ECC R-DIMMs need to initialize memory registers embedded in the R-DIMMs during boot-up and it adds 30-60 seconds to the boot time. Once initialized, the memory controllers in the CPU then communicate with these memory registers which in turn are responsible for storing and retrieving information stored in memory.  This substantially reduces the workload on the memory controller in the CPU but adds an extra step for reading/writing to memory.  Unbuffered RAM has no memory registers and CPU memory controllers need to work harder to access memory directly.  Unfortunately, if you want the benefits of Registered ECC memory, longer boot times are the unavoidable price you'll pay.

Workstations with PCIe RAID controllers and similar devices with their own BIOS will further increase boot time, sometimes taking minutes rather than seconds. 

I un-installed intell DSA  (Jan-2023)

https://www.intel.com/content/www/us/en/support/articles/000089221/software/software-applications.html

I Boot thru SSD (NVME) Windows 10 Pro and with as less as possible programs enabled on Start-up I lowered Timing from Push Power button to  windows 10 startup- loging screen from 1 min 22 sec down to 33-35 sec .