iMac 2009 early external monitor resolution
Hi!
I have iMac 2009 Early, and a Samsung SMEX2220 Monitor. Today i bought a Mini Display -> VGA cable http://approx.es/APPC13#.VgW9UI_tmkp. I connected to the mac, but the highest resolution offered is 1360x768 however the Samsung is a full HD capable monitor. The cable also supports this resolution. I tried to hold down the option key, and click on resolution but nothing happened. I tried resetting the PRAM and SMC after that, i realized that 1920x1080 appeared, when i tried to change the resolution the screen gets black, and flickered. After that the resolution went back to 1360x768. I also have a Samsung TV LED 32" in my home, i tried with it, the same...
So the problem is not with the monitor. Maybe the MiniDisplay port, or the Cable. Any other Suggestions?
Thank you.
iMac, OS X Yosemite (10.10.5)