LCD 75Hz refresh rate

nicoliani

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LCD's are standard 60Hz refresh rate. But you can increase it to 75Hz to get better image quality in games.
What I wonder is if the increase will have a negative impact on the monitors input lag? If it takes e.g. 40ms for the image to show up at 60Hz will it now take e.g. 70ms?

Besides DVI is cut at 60Hz. Anything above 60Hz it have to send the image twice like 50Hz+25Hz.
What the standard of the DVI for 60Hz does it send the image at 60Hz or does it go by 30Hz+30Hz?
 

ToastyX

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DVI is not limited to 60 Hz. DVI can handle any refresh rate as long as it fits within the bandwidth.

The problem is most LCD monitors don't support 75 Hz properly. Most will still output only 60 frames per second by skipping every 5th frame. The only LCD monitor I've seen that doesn't do that is the Samsung 226BW. There are probably others, but I haven't seen any myself.

Raising the refresh rate should not have a negative impact on lag. It should actually reduce lag if it works properly.
 

nicoliani

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It was in another article, I can't remember where.
You said skipping every 5th frame, how is this noticed in games?

In the link I posted in the in there in the last page they are talking about 100Hz and input lag. This was 2006 and they just noticed input lag. What the writer tries to say is that the 100Hz TV they tested produced an input lag around 40ms. And if I get it right he refers that because of the 100Hz. But all LCD's have a natural input lag because of technical limitations, and a screen that is 24' it's very normal that the input lag lands on 40ms or even higher no matter if it's displayed at 65Hz or 100Hz.
 

ToastyX

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That's not the same. Those 100 Hz HDTVs aren't really 100 Hz. They're 50 Hz with intermediate frames added by an image processor. The image processing along with overdrive adds lag. It really shouldn't lag that much, but Samsung displays with S-PVA panels tend to lag more than they should.

The monitors that skip every 5th frame at 75 Hz actually receive 75 frames per second but only display 60 of them. That makes motion appear jittery. It's very noticeable to me just by moving the mouse. It's also easy to see with scrolling text.
 

nicoliani

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It looks bad with 75Hz for Windows. In ATI CP I have an option so 75Hz is triggered when an 3D application is started like a a game. In games the image quality gets impressive compared to 60Hz but still the text gets little blurish but not annoying.

Will there come computer LCD's with higher standards than the 60Hz?
 

Nielo TM

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That's not the same. Those 100 Hz HDTVs aren't really 100 Hz. They're 50 Hz with intermediate frames added by an image processor. The image processing along with overdrive adds lag. It really shouldn't lag that much, but Samsung displays with S-PVA panels tend to lag more than they should.

The monitors that skip every 5th frame at 75 Hz actually receive 75 frames per second but only display 60 of them. That makes motion appear jittery. It's very noticeable to me just by moving the mouse. It's also easy to see with scrolling text.
100/120Hz LCDs are actually refreshing at that rate. Otherwise motion compensation wouldn’t work.
 

Nielo TM

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LCD's are standard 60Hz refresh rate. But you can increase it to 75Hz to get better image quality in games.
What I wonder is if the increase will have a negative impact on the monitors input lag? If it takes e.g. 40ms for the image to show up at 60Hz will it now take e.g. 70ms?

Besides DVI is cut at 60Hz. Anything above 60Hz it have to send the image twice like 50Hz+25Hz.
What the standard of the DVI for 60Hz does it send the image at 60Hz or does it go by 30Hz+30Hz?
Standard LCDs display each for 16.6ms. The lag is however is caused by pixel response time and other elements that drives the LCD.

DVI supports multiple refresh rates and resolutions (but, 1920 x 1200-60Hz is the limit for single-link DVI). The problem however lies in the display device.

PS: It would be more helpful if manufactures take PAL countries into account before locking the monitors at 60Hz.
 

SoAndSo

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226BW can accept and display 75Hz via DVI and HDMI but, it needs to be forced from nvidia CP.

how do i do that? ive tried looking throught the CP but i cant see any way how to

PM me with the answer please as i know ill forget to look here again :>
 

Nielo TM

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Go to manual/custom timing on nvidia control panel. Then add a profile. When a pop-up appears, enter the resolution (1680 x 1050), refresh rate (75Hz) and color (32bit). Then click on test and click on OK.

Click on the profile you’ve just created and click on apply. If that doesn’t work, you can select 75Hz on the windows display property under advanced.
 

buffbiff21

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With active matrix LCDs it's not going to matter.

Maybe with something like DVDs, since 24 doesn't go into 60 evenly, there's going to be some minute screen tearing. Or if you like to see more of your mouse cursor when you move it quickly across the screen.

But still. Refresh rates over 60hz on LCDs are just pointless.
 

lillimon04

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I run my 940mw at 75hz and it looks perfect. But you can only do it after windows does an update for the monitor, or if you get the new drivers for the monitor by yourself.
 

nicoliani

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- finally, 2007 may see the arrival of a new generation of screens at some unknown date and price. There will be TN 1 ms panels (will this be real progress in reactivity? We don’t think so.), LED backlighting for a wider gamut (the first, the XL20, will be released shortly for 1400 Euros), and finally 100/120 Hz screens. These last ones should noticeably improve rendering in games, but will they actually make an appearance in 2007 or 2008 ?
Or maybe 2009?
 

shurcooL

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With active matrix LCDs it's not going to matter.

Maybe with something like DVDs, since 24 doesn't go into 60 evenly, there's going to be some minute screen tearing. Or if you like to see more of your mouse cursor when you move it quickly across the screen.

But still. Refresh rates over 60hz on LCDs are just pointless.
Of course it matters. With higher refresh rates, you could turn on V-Sync in games and enjoy higher FPS without the tearing of frames (as it happens with V-Sync off).
 

nicoliani

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Just got a mail from a manufacture, where I asked if they soon would ship 100Hz monitors. The answer not in the year to come, no plans.
 

LawGiver

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well my vx922 does in fact operate @ 75hz. I know this because in any game that is not fps locked, TF2 for example, when I set vcync ON, it never go above 75 fps if I set refresh rate to 75hz. likewise it will never go above 60 fps if I set refresh rate to 60hz.
 

ryan_975

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well my vx922 does in fact operate @ 75hz. I know this because in any game that is not fps locked, TF2 for example, when I set vcync ON, it never go above 75 fps if I set refresh rate to 75hz. likewise it will never go above 60 fps if I set refresh rate to 60hz.
Just because it accepts a 75hz signal from the graphics card doesn't mean that the monitor is actually displaying all 75 frames. For instance, my 20.1" can accept 75hz, my games will run at 75FPS when I have Vsync on, but if I bring up the menu on my monitor it'll still say 60Hz
 
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