We have the same Configurations for both the 7480 and 7490s however from an Off state to the Desktop, the 7490s take ~65-70 Seconds where as the 7480s take ~25-30 Seconds.
Both are running SSD SEDs as well as 8Gram.
Is there something that I am missing here?
Look forward to your responses
It would help to identify where the extra time is occurring. If it occurs before you see the spinning dot animation, then the extra time is being incurred during POST. If it's occurring after the spinning dot animation, then the extra time is being incurred while the OS loads. If it's the former, go into your BIOS settings and look for an option called Fast Boot; its options should be Minimal, Thorough, or Auto. May want to compare those settings across your systems. If it's the latter, then maybe something going on with your SSDs? As a test, try swapping an SSD currently in a 7480 over to a 7490, reimage it, and see if the 7490 starts booting faster.
If you have a NVMe ssd, you should give a try to put your drives in AHCI mode instead of RAID, and to use the latest available NVMe drivers from Toshiba/OCZ.
I was able to get much more performance this way.
Not sure if it will solve your issue.
Edit: you can get more details here : https://www.win-raid.com/t29f25-Recommended-AHCI-RAID-and-NVMe-Drivers.html
Edit2: You should also upgrade the firmware of your NVMe drive (you can get the package from Dell support center)