Dell Precision M3800 - keyboard and mouse bug

I SINCERELY APOLOGIZE FOR THE ALL CAPS> my computer keeps switching in and out of CAPS lock and it has gotTEN TOO FRUSTRATING TO KEEP THE CASE OF MY TEXT CONSISTENT< SO BEAR WITH ME>

I PURCHASED MY M3800 in December of 2014 and it was working fine, until I HAD TO CALL DELL SUPPORT TO REPLACE THE MOTHERBOARD AND POWER JACK BECAUSE OF BATTERY ISSUES> 
SINCE THEN I HAVE EXPERIENCED THIS BUG on and off, affecting several operations of the keyboard and mouse.

the BUG SEEMS to be triggered by any time i press the shift key. However it seems like it can be triggered by more ways than that, and may often trigger randomly. 

When the bug is triggered ANY LETTER I PRESS IS IN ALL CAPS UNless i press the caps lock buttoN>
NUMBERS DO NOT TYPE EITHER< !@#$%^*() WHERE ALL THE NUMERICAL CHARACTERS TYPE AS IF I WERE HOLDING SHIFT AS I PRESSED THE KEYS> 

MY ABILITY TO SELECT WITH THE MOUSE IS ALSO AFFECTED: WHENEVER I CLICK ON A PAGE IT SELECTS EVERYTHING ELSE PRIOR TO WHAT I HAVE SELECTED> (FOR INSTANCE IF I CIICK MY CURSOR TO THE TOP OF THIS TEXT IT WOULD SELECT EVERYTHING I HAVE TYPED TO FAR)
AND IF I CLICK ANY ICON OF A RUNNING PROGRAM< IT CREATES A NEW WINDOW OF THAT PROGRAM INSTEAD OF RETURNING TO THE EXISTING PROGRAM>

THIS BUG IS EXTREMELY AGGRAVATING TO SAY THE LEAST> I HAVE TRIED ALMOST EVERYTHING TO TRY TO GET RID OF IT> REINSTALLING DRIVERS< REFRESHING WINDOWS< REINSTALLING WINDOWS< AND UPGRADING TO WINDOWS TEN> BUT THIS BUG HAS PERSISTED THROUGHOUT ALL OF THOSE CHANGES> 

HAS ANYBODY ELSE EXPERIENCED A BUG LIKE THIS? AND IF SO HAS ANYBODY BEEN ABLE TO SOLVE FOR IT?

THANK YOU FOR YOUR TIME