black screen multiple times a day

[speedspeed]

yesterday I had in my notification screen some update
I think Samsung update or something it said
I pressed update
later the phone freezed and I had to pull the battery

since then I have multiple times a day black screen
I hear the unlock screen come when you press the button, but only see black screen
and need to pull the battery to get screen working again

any ideas?

 

[sydneycooper1979]

Have you tried a factory data reset?

 

[speedspeed]

not yet
tried to avoid
but no other option I guess?

 

[speedspeed]

ok did a factory reset
with almost nothing installed, only apps which are really crucial
but same problem

now sometimes also the screen goes funny, like if you have a bad video card in pc the screen goes like all twitching
don't know how to explain really

ps. I made some screenshots, but the screenshots are fine so its just the output or something
since on the screen it went crazy

this means its the end?

 

[speedspeed]

http://s33.postimg.org/yg92r4w5a/IMG_20160524_161051.jpg