Help My Sony Hmd A240 Monitor Cant Do Anything Above A 60 Hz Refresh Rate?

[Felony 301]

BASICALLY MY MONITOR WONT GO ABOVE A 60 Hz REFRESH RATE NO MATTER IF ITS PUT ON 85 HZ LIKE BEFORE. I NOTICED IT NOT DETECTING MY MONITOR LIKE BEFORE WHICH USUALLY SAID PLUG AND PLAY AND SOMETHING ELSE SO I DOWNLOAD DRIVERS FROM SONY AND NOW IT READS IT RIGHT BUT STILL DOESNT SAY PLUG AND PLAY AND IT STILL DOESNT LET ME DO ANYTHING ABOVE 60 HZ REFRESH RATE. ONLY THING THAT WORKS IS 43 HZ INTERLACED AND I TRYED DIFFERENT RESOULTIONS BUT NOTHING WORKS.I USUALLY HAVE IT ON 1024X768 AND IT COULD DO 85 HZ BUT NOW IT WONT LET ME EVEN IF ITS SAYS ITS ON 85 HZ ON THE COMPUTER BUT THE MONITOR STILL STAYS ON 60 HZ.I ALSO TRYED SONYS METHOD OF SELF TEST ON MONITOR AND IT WORKS SO I DONT KNOW WUT TO DO. ANY HELP WOULD BE APPRECIATED BECAUSE IT REALLY STARTING TO HURT MY EYES LOL!!!! OOPS ITS A 17 INCH MONITOR!!!!!

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