Windows "randomly" spending WAY too long on Welcome screen. Pls help!

Hi everyone.

I had this PC for the longest time, and everything seemed fine until a couple months ago I started having this issue, which I hope you may be able to help me with.
The thing is, in what appears to be random fashion, Windows takes an unacceptably variable amount of time in the Welcome screen on each startup.

The usual time spent on this screen is some 6 seconds (2 full cycles of the twirling dots animation). Now, the thing is, if you constantly reboot the PC, without changing anything, the time spent on that screen will vary, apparently at random, between the usual 6 seconds it used to take, up to THIRTY seconds. This variation, needless to say, makes it an even bigger pain to troubleshoot.

Other than that startup delay, performance seems fine in every other scenario, even gaming, both in 3D performance and load times.

Another thing to note is that it only happens on boot. Logging off and back on takes the expected time, so contrarily to what it would seem, it doesn't seem to be related to the logon itself.

Stuff I've tried:
- Reset of RAM to default 2133 MHz (normally running 3200)
- Resetting BIOS to defaults
- Reflashing BIOS to version prior to when the issue started
- Clean install of Windows
- Clean install of release version of Windows (I'm normally on Insider Fast)
- Installing Windows to either hard drive and NVMe SSD
- Creating a second Windows user
- Removing all unneeded peripherals
- Disabling SATA controller, leaving only NVMe storage
- Switching to Performance power profile
- SFC /scannow
- Disabling Hibernation (and therefore Fast Start)
- Disabling everything in startup using Autoruns (while it does increase the chance of getting lower times, I don't consider the results to be conclusive at all)
- Currently I'm unable to test Safe mode since it GSODs in the Windows build I'm in but IIRC it improved load times a lot too, not sure if it would ever take longer than those intended 6 seconds

The PC:
- Ryzen 5 3600
- ASUS Prime B350 PLUS
- 2x8 GB G.Skill FlareX 3200
- AData 8200SX NVME 1 TB SSD
- 4 TB SATA 3.0 HDD
- RTX 2070
- Thermaltake TR2 600W PSU
- Windows 10 build 19577

Latest BIOS and drivers on everything.
No overclock other than RAM at 3200 using XMP.

I have dedicated more time to this issue than I'd like to admit and it's driving me insane.
The only thing I could think of right now would be swapping the mobo or PSU, but that's just a stupid desperation move, which would probably accomplish nothing.

I'll greatly appreciate if anyone could provide me with any pointers as to what could be going on here.

Thanks in advance!

EDIT: Setting HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\VerboseStatus to 1, the message that sticks there forever is "Preparing Windows". Any ideas?

Hi, a couple of important options are clearly unavailable. As it's an Insider build, naturally anything could happen. If you wished. you could try installing a 'stable' retail build e.g. on a different disk for comparison.

If you wished to try to identify the issue with your current build (which no doubt will change fairly soon) you could try using this
Download and Install Windows Performance Toolkit in Windows 10

However you may find that technical and awkward, although it gives detailed graphics and helps to identify e.g. driver-related delays in booting etc.

There are some threads on tenforums with illustrations of it in use. Just search for performance analyzer.

I'm confused. You stated - Windows 10 build 19577 in post #1.

So you are saying that using 1909 your PC does this?

- Currently I'm unable to test Safe mode since it GSODs in the Windows build I'm in but IIRC it improved load times a lot too, not sure if it would ever take longer than those intended 6 seconds

You said at the beginning:

I had this PC for the longest time

Did this problem start after any particular upgrade - in particular a driver-related upgrade?

If you tried an older build on Win 10- say 1809 or 1903, I wonder if you would still see the same issue.

The tool I mentioned above is the one that will give you the detail you seek. However it is not the easiest thing to deal with on a on-off basis.

Tonyb said:

Have you installed the latest optional update by chance, Its a bug in the latest optional update been hearing about it allot threw other forums and tech news stuff, it can even throw a black screen when first booting for some time, and delayed boot up times.

Good thought: see:
KB4535996 CU Win 10 v1903 build 18362.693 and v1909 build 18363.693

and in particular
https://www.windowslatest.com/2020/0...-10-kb4535996/

According to numerous user bug reports picked up by us, Windows 10 KB4535996 has several critical issues. As per the user reports, Windows 10 KB4535996 may have the following serious bugs:

• Slow boot: After the power button is pressed, Windows 10 takes a long time to boot to the lock screen and login time has also increased. Task Manager reveals that Windows 10 resources are under normal usage.