37pfl5405h/12 hdmi random black screen
Hello guys!I have a television 37pfl5405h/12 and i connected to my pc with hdmi cable.My video card is amd hd 4870x2.First time i was getting some random black screen at every five minutes,that last 2 seconds.Next i upgraded the tv firmware version to the newest and all went well no black screens. But after i use my tv for 2 hours or 1 hour or 3 hours my tv gets the black screen wich last 2 seconds and after the picture come back. I have tried different hdmi cables , no cable seems to correct this bug.Before i have upgraded tv firmware i was getting a lot of black screen , but the problem didn't dissapeared , this is why i think it can be solved with firmware .Resolution is set at 1080p 60hz, tv is set at pc mode.Please help me to resolve this problem. The problem occures only with hdmi , not when i watch cable tv. Sorry for my bad english.Thank you.