mobile

Hi there, first, sorry for my english but I'm trying ;)

I have a problem(solved probably many times but it isn't working for me, am I doing something wrong?).

So, from beggining. Few days after update my SGS4 to 5.01 Lollipop original(I've never modified this phone), I've got a problem with physical keys, there were no answer from all of them(include menu and back key). So, to check if it is hardware problem, I've get thru download and recovery mode - working, but in recovery mode I couldn't move thru volume up/down buttons(there was no answer from them).

So, decision, flashing by official firmware. I've downloaded this one( I9505XXUHOB7_I9505XEOHOB3_I9505XXUHOB7_HOME ) and then, fun has gone thru pain in ass. After flashing thru Odin, phone is showing logo for a dunno, 0.5 second and whole screen get's dark. Like it couldn't get to whole booting sequention. The same when I'm trying to get to recovery mode. Even there is no blue sign up in the screen...

Now the question, what I'm done wrong? I've tried with pit file and nothing else happen. Can someone pls tell me what should I do, what should I download and flash?

And sorry to mods for post in general category but I cannot put this(or even ask in relevant question) in proper section...