I'm the owner of ASUS ROG GT751JT laptop since two days. Unfortunately, I've been experiencing unpleasant crashes of almost all applications.

Silverlight addon in firefox crashed multipled times, sometimes after 2 minutes sometimes after an hour, but eventually I did not watched any stream without a crash.. Skype usually crashes after 2 minutes of video converstation.
Blizzard Heroes of the Storm is usually crashing 1-2 times per game (I have not experienced this on any other computer before). Even Mozilla Firefox,crashes sometimes without a reason. Here is few things that I have already done.

I checked and unchekced .NET 2.0 and 3.5 in Programs and Features menu in Windows.
I've updated audio and intel drivers and uninstalled ROG Gaming Center and Gaming Fist.
Installed all the updates to Windows 8.1 from Windows update.
I have newest NVidia drivers (date 02 May 2015). Almost all software is up-to date since computer has literally two days.

After those tweaks, I'm not experiencing reboots as it was before.
Does any of you have idea what might be the reason ? It's the first time I'm experiencig issues like that on any computer ever had.

Update 03/05/2015
I've made clean Windows 8.1 installation from recovery partition - still the same.