I buy Samsung P2250 last week , and I have windows xp , windows 7 ultimate and Linux Mint8 , my graphic card is Nvidia G-Force 8500 and my mainboard is Asus M2N-PLUS SLI , but in three OS , I can not change Refresh RATE and in all OS maximum Refresh rate is 60 HZ and I can not change it to 75 HZ , so I do have good picture and it make problem for my eyes, I change resolution from maximum to 1280x1204 and 1024x768 , but refresh rate is still 60 HZ what is problem ? and how I can solve it ?
You are confusing CRT with LCD. In LCD the refresh rate doesn't change a thing with the backlit light, only the speed of the refreshing the LCD panel itself. Most LCD panels are 60Hz. LCD monitors that takes 75Hz are for VGA purposes, as it's an analogue signal... it can provide sometimes a better signal (digital doesn't have quality loss, it's either 1 or 0's.. it works or doesn't). Despite going at "75Hz" with the supported monitors, their panels are still 60Hz at the end. LCD image doesn't flicker.. it's the back light to illuminate the LCD panel that does.. and their is nothing you can do about it... even if you could set your monitor to 1 xillion Hz.. the lamp will still be at 60Hz rate. The only thing you can do to change this, is get a LED backlight LCD, where they CAN support different refresh rates.. on laptops they usually supports 40 and 60Hz, where 40Hz is there to save battery life even more to what LED provides over CFL's (normal backlight bulb of LCD). LCD is a digital technology.. if you use a VGA cables that means that your graphic card converts a digital signal into VGA, which your LCD internal processing converts back to digital (loss in image quality right there, and creates input lag). In CRT, it's all analogue, you are actually changing the rate of the cathodes refreshing (speed of going from off to on). Such case, a 85Hz is recommended as bare minimum for proper monitor usability without headache. 150-200Hz could be found on the latest and highest-end CRT's at it's native resolution. It make it look like you are looking a peace of a paper, pretty cool stuff. Most CRT's that people had where 85Hz.. those who put it lower did not use the native resolution, got crappy display, or never configured the damn thing. Your P2250 is a 60Hz panel.. so 60Hz is what you get and have. Windows 7 might identify it as 59Hz... that is 60Hz, since reality it's 59.997Hz... which is 60Hz (Win7 rounding bug - ignore it, should not affect your display (if you look at the display information via it's menu, it will say your current resolution as well as 60Hz)) . If it was really sending 50Hz then you wont' get an image on your screen.
I didn't think the refresh rate on LCD monitors made any difference. I can't see any reference to refresh rate in the specifications on the Samsung webpage, have you tried contacting Samsung directly?
Thanks I use DVI cable and do not use VGA cable so I think you said I must use analog cable my english is not very good
VGA cable on SUPPORTED displays. Some takes VGA but still take 60Hz. And I would like to UNDERLINE, that VGA with LCD is VERY BAD (input lag, and signal loss of quality), and will not change anything at the end (just a grainier.. less clear... picture). The 75Hz VGA input has been added in some monitors to try to diminish the graininess and increase sharpness, in teh case that you really must use VGA and not can't use DVi for a certain reason. DVI (or DisplayPort or HDMI) will provide you with the best image quality, and the least amount of input lag.
Thanks again So what I must do with this problem , I had this problem when I had CRT monitor and Refresh rate was 60 and I changed it to 85 HZ and everything is good and it can not make problem for my eyes right now the LCD make problem for my eye and I have headache
LCD panels do not flicker at slow refresh rates like CRT screens do. If you are getting a headache it has nothing to do with the refresh rate.
stop starring at your screen for so long and takes breaks if you start to get a headache when on the PC. but as pookey said probably have nothing to do with the refresh rate
Have you turned down the brightness and contrast to sane levels? Most LCD's come with crazy amounts of both which is a pain.
This is most likely what's happening. Or that the Panel isn't too good and you're getting tons of Dithering.