Of course you know the first reply is always to find out what you have and haven’t tried so far.
How much ram do you have in the rig?
There is a simconnect issue that will do just that, or CTD with 16 gig users (with that much in hardware, I suspect you are good in that respect though)
One starting point is to empty any and all content from your community folder.
Add-on mods liveries and sceneries have been known to cause this.
I can’t imagine it is hardware related, but you should disconnect those and prove that it isn’t.
There are some very good articles in the “support” section at the top of each page to start with solving this “looping start” issue.
Let us know how you make out.