Sudden problem with video playback and GPU fans - HD4780

[TheBenjamin]

Hello,
I have PALIT Radeon HD4780 1GB.
everything was fine but suddenly when I tried to play videos I had black screen and only audio.
trying to play video at XBMC was simillar just with green screen.
when trying to watch youtube videos green screen again.
youtube got "fixed" after disabling hardware acceleration but when watching full screen the video is like in slow motion.
at XBMC I disabled dvxa2 hardware acceleration and then I get video but again.. jittery and not smooth.
I meesed with my codecs and now youtube and xbmc is fine but when trying to play mp4 in WMP i get just sound.

in overall I started to hear the GPU fans working on full speed alot more often and in weird times like windows startup or just browsing the web when there's no any substantial graphic demands.


I tried to reinstall codecs/drivers.

any ideas? I'm clueless.

Thank you.

[atomBomb]

Maybe its time for new GPU.. I once had 4970 that gave the smoke spirit out, not saying its all of em but it was under 2 years old..