You say your computer is almost brand new...and I would imagine under some form of warranty.
A new computer should not be presenting with the problems you have listed - & we volunteers should not be putting at risk the rights,YOU, the consumer has under that warranty...
Be aware that attempting any subsequent hardware troubleshooting steps may, in some cases, void your warranty.
I strongly suggest that you should seek further advice asap.
Under Warranty terms a duty of care applies.