Solved Windows 8.1 startup apps wait 90'' before loading

Hello,
since 2 days my PC startup normally, beside the fact that after desktop appears, almost all startup apps wait 90'' before loading.

Looking into task-manager, there is no process hanging on the CPU or disk I/O.
Everything is steady, I can even see that some of startup apps are already running in the Process tab (e.g OpenHardwareMonitor) but with very low RAM usage.

After waiting about 90'', RAM usage of already running apps start to grow, and others apps appear both in the taskmanager and in the taskbar in a few seconds as usually.

It's like there is a waiting period before startup apps are allowed to start

I've already tried this whit no luck.

Since the problem appeared 1 or 2 days ago (I don't remember exactly) I've also thought about some bad Windows Update, and I tried to uninstall the last 4 updates.
And there it is something interesting: after being prompt to reboot, Windows reboot quite fast, then stays for about 60'' on the classic "Configuring your system" screen.
When "configuration" finishes, my desktop load and ALL the startup apps also load, immediately with no delay.

However when doing a dry reboot or a normal shutdown->powerup, the problem is still here.

The only application that I've recently installed is OBS, which I've already tried to uninstall, with no luck.

This behavior is driving me crazy, especially because if I manually launch one of the startup app during the "waiting period", it loads and opens immediately!

Can you guys help me?
Thanks

EDIT: Sys specs
OS: Windows 8.1
CPU: Intel 4770k
MB: Asus Z87 Deluxe/Dual
RAM: 16 GB
GPU: EVGA Nvidia Geforce GTX 780 Classified
SSD#0: 500GB Samsung 850 EVO (primary os boot)SSD#1: 500 GB Samsung 840 EVO (data storage)

Ok, after a deeper analysis, I found that:

Gobbo said:

The only application that I've recently installed is OBS

Click to expand...

IS FALSE!

At least, OBS was the only application that I've manually installed.
However, sorting Installed Applications by Installation date, I found that NVIDIA Geforxe Experience has updated itself to the latest version.
And guess what, this version is causing my problem.

After uninstalling it, the problem is finally gone.
In the official Nvidia forum there is a Feedback thread where tons of users are reporting this behavior, and also suggesting some solutions, rather than uninstalling:


Since I need GFE I will try to see if one of this solutions is working for me too