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doublejdog
05-20-06, 07:56 AM
Is it better to have my refresh rate set to 60hz or 75hz when gaming on a LCD monitor. Thanks.

Greg
05-21-06, 12:33 AM
Is it better to have my refresh rate set to 60hz or 75hz when gaming on a LCD monitor. Thanks.
Apparently 75hz is better for a couple of reasons. Explanation: http://www.microsoft.com/whdc/archive/TempRate.mspx
(LCD reasoning is mentioned as part of this larger article.)

squall_leonhart
05-21-06, 12:39 AM
the higher your resolution the less you see flicker...

SLippe
05-21-06, 01:32 AM
Depends if your monitor is Digital or Analog. My LCD is Digital and I can only set it to 60Hz. If I set it to 75Hz, I start getting little colorful dots on my screen. If you have an Analog LCD, then set it to the max that you can.

squall_leonhart
05-21-06, 01:52 AM
LCD whether analogue or digital is made up of little crystals which light is passed through.

but LCD doesn't really need a refresh rate.. what matters with LCD's is response time.

the lower the response time. the sharper the image.

high response times can cause ghosting

doublejdog
05-21-06, 01:31 PM
Thanks. I have a dell 1905FP and if I don't install the windows update driver I can use 75Hz using the digital connection. If I install the monitor driver it will only let me use 60Hz. Does anyone else have "dots" when using 75Hz and DVI? I Haven't tried yet.

OWA
05-21-06, 01:43 PM
Interesting link. Here is a section that talks about it (from the link):

Leaving aside the temporal rate conversion difficulties, displays with a sample-and-hold characteristic, such as LCD and plasma, would produce better motion portrayal if operated at rates above 60Hz. Flat panels are normally run at 60Hz, because it is perceived that this is all you need to do since there is no flicker problem. The reality is that a faster update rate would be beneficial in order to reduce the blurring effect associated with the sample-and-hold characteristic. Pixels with a sample-and-hold characteristic effectively extend what should have been an instantaneous sample into a constant value that lasts for a whole frame. The result of this is motion smearing. This smearing is reduced if you can update the sample and hold circuits more often with new sample values.

There are two reasons why LCD and plasma displays almost all currently operate at 60Hz. Least importantly, the drive electronics only goes that fast. More importantly, there is no standardized faster rate, and the drive electronics designs are all designed for single frequency operation. LCD manufacturers would like it if there were a higher rate standard such as 75Hz, but they won't use it, as there is no standard.

OWA
05-21-06, 01:50 PM
I added a custom resolution so I could use 75hz for the refresh rate (since the specs on the 2405 said it should support it). It seems to be working fine.

Edit: Although I can set 75hz for the desktop, I'm having some trouble getting that custom setting to be used in games.

MadKent
05-21-06, 01:55 PM
On LCD monitors the best resolution is always the native resolution and the best refresh rate is, quite simply, the one that looks best. Unlike CRT's refresh rate has no effect on flickering with LCD's. Like someone else said above IQ is affected by response time and there is nothing one can do about it if response time is too slow.

Mike89
06-01-06, 12:40 AM
There is another reason I like 75hz better for my LCD in games. Sometimes when using 60hz with vsync off, I see tearing when the games exceeds 60 fps. Setting it to 75 gives me a little more head room before tearing occurs with vsync off (75 fps before tearing vs 60 fps). Vsync is very tempermental. It's trying to figure out which game works best with it or without it (depending on game, game settings, system speed). Play with vsync on and have a constant frame rate as long as the fps doesn't drop below the refresh rate (which then results in fps being half of refresh rate) (triple buffering helps here but not all games work with it) or playing with vsync off and not having to worry about the half drop in fps but then experience some tearing if the fps goes too high.

Even though as a whole, I do like my LCD better than my old CRT, but with the CRT I never saw tearing (at least I never noticed it) with vsync off because I used a refresh rate of 100hz.

One of these days someone is going to figure out how to completely eliminate vsync altogether where the display and video card will be in harmony and able to run where ever the hell it wants to without any visual effects. I for one will welcome that day.

Xion X2
06-01-06, 01:26 AM
Set it to 75 if your LCD supports it. 75 will give you your quickest response time in sync'ng with your mouse movements.