Refresh Rate Problem

[voodoomelon]

My computer is nearly a 2 1/2 years old now, and the whole time i have been running my desktop resolution at 1280 X 1024 @ 85hz.
However last week my monitor suddenly dropped down to 75hz for some unknown reason, and i find this uncomfortable and it has been like this ever since. My monitor is as below, and in display properties the refresh rate is set to 75hz, with the option "Hide modes this monitor cannot display" enabled. Should i disable this and just set it to 85hz again, or is that too risky?
Could all this be due to overheating of my Geforce?
Thanks!

 

[CyberFed]

I'm not sure why it mysteriously dropped down to a different refresh rate but if your monitor doesnt support 85Hz its better not to run it at that after awhile the monitor will begin to kinda shake at the corners rapidly which is no good

 

[o770]

well check for the proper monitor driver in the device manager. depending on how you mess around with other drivers sometimes windows will lose the monitor driver, so, if yours have a plug and play driver it would be better to install the proper one.
if youre sure you have always used the 85Hz for that resolution you can safely try setting it to 85, if the monitor not supports it you just wait for Windows to restore the previous refresh rate.

 

[BadThad]

Did you install the monitors INF file? ...or is it using "PNP Monitor" or "Unknown Monitor"? Whatever, make sure it has the proper INF loaded for that monitor. Then, only use settings listed in display because that's all the monitor can handle without damage to it.