Black screen problem

Hello,

I got a problem. it started yesterday, I opened my computer and it was very slow. I wait like 10 minutes but computer was starting windows. I left my computer open and I get back after 3 hours. After those 3 hours (I don't now how fast) my computer was in Log in mode. Log in was slow and I shut down the computer after 15 minutes.

After that always when I start my computer at first it ask Safe modes (different kind of safe modes) or normal start. If i take normal start there comes "starting windows" text and that windows image. After that the screen goes black but I see my cursor.

If I go to safe mode, it loads windows files and then goes also to that black screen. I have tried all kind of safe modes.

I have tried "last known good configuration". With it i can go to login in mode but login is very slow (sometimes it doesn't go to login mode and freeze with that blue windows log in background)

My computer is Acer Aspire 5532 and I got windows 7 on it. I don't have the windows 7 instalationcd so the formation is not good solution.