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xmichaeluk
02-17-08, 04:23 PM
Hello everyone! I've a little question to our experts. I am wondering whether the refresh rate of a monitor or the one set in a game has an affect on the fps during game.

I've changed my refresh rate from 60 to 75hz and have noticed a great improvement since my headaches are gone and my eyes are not aching anymore. But does this affect the amount of fps?
Is this what I'm thinking? - Bigger refresh rate - less fps
smaller refresh rate - more fps?

Can some explain this to me?

Thanks guys!

XDanger
02-17-08, 04:46 PM
What resolution do you play at and what monitor is it, Im sure you can do better than 75hz

Higher is better please just leave it at that.



but the puter spits out the same fps no matter what the Hz is unless you have v-sync enabled.

xmichaeluk
02-17-08, 04:49 PM
1440x900 I've a Iiyama ProLite E2001WSV and a GeForce 8800GTS 512

So, I presume refresh rate has no influence on the fps?

SlieTheSecond
02-18-08, 01:22 AM
1440x900 I've a Iiyama ProLite E2001WSV and a GeForce 8800GTS 512

So, I presume refresh rate has no influence on the fps?

As said above, no. Not unless you have vsynch enabled. Vsynch will synchronize the fps with the refresh rate to prevent screen tearing. With it off, your fps will remain unchanged.

Anything below 70hz usually gives people headaches (with a crt).

xmichaeluk
02-18-08, 02:35 AM
But when it comes to lcd, can you notice a difference?

stncttr908
02-18-08, 02:55 AM
My LCD supports 75hz, but I don't notice a difference.

xmichaeluk
02-18-08, 03:18 AM
Yes, I've read it's a different story when it comes to refreshing rates in lcd monitors. It is recommended that you keep the rate at 60hz since anything higher than this may even cause damage to your monitor.

Thanks for help

EciDemon
02-18-08, 03:37 AM
Higher is better, ... but only for CRT.

If you got LCD stick to 60hz, LCD monitors might support 75, but they only output 60hz, and in some cases it can even result in quallity loss due to conversion that takes place. On CRT refreshrate is important as the whole screen has to be redrawn each time as after each "bombardment" the screen goes black again, so 60hz = 60 complete screen redraw's per second. Therefore you want higher refreshrates on CRT, so you dont see the flicker.

LCD on the other hand will not redraw the whole screen, only those pixles that has changed, and pixles dont go black 60 times per second either, they are constant in luminance/color, thus no flicker and no reason to go higher then 60hz. (I guess 60hz is standard on LCD due to bandwidth limitations)

So im a bit puzzled about your headaches, with CRT sure, not with LCD, they dont flicker.

What you want to do is to stick to 60hz, and use vsync to remove screen tearing. If you messure FPS at this point it will never go higher then 60 as it is locked, but it is more then enugh as long as your hardware can cope.
In the case where the puter can not output 60fps in vsync the fps will drop in half untill it can sustain it again at 60. If yet again it can not sustain at 30, it will drop to 15 and so forth. So with gfx intence games, or for benchmarks you want Vsync turned off.

Also, for LCD, if you have the option to use a DVI cable, use it. That will ensure you get no quallity loss what so ever.
Your gfx card, is digital, CRT is analogue, VGA connector is analoge.
So your GFX card outputs 1's and 0's, but CRT/VGA can't handle that so a Digital to Analoge converter (DAC) is precent in the gfx card to convert those 1's and 0's to an electrical curent, perfect for CRT as the whole thing is analoge. However your LCD is digital, so with VGA cable, where the signal is now analoge the signal must again be converted back to digital. So there are two stations where you get a signal degregation (dac in gfx card, and the analoge to digital converter in your LCD)
Ontop of this, LCD's can have a hard time to align the pictures Pixles with the LCD monitor's pixles, thus you get a somewhat blurred image. This is normal, as this is how LCD's interpolate an image to look "best"

But, DVI is Digital 1's and 0's all the way, just the way LCD likes it :)
and the LCD screen has no problem aligning the image with the pixles of the monitor.

So to sum up:
Use 60hz
Vsync ON, _if_ your computer is fast enugh or if your not playing Crysis ;)
In all case where it's possible use the resolution your LCD is designed for (for a perfect pixel to pixel match)
Use DVI cable.

XDanger
02-18-08, 08:46 AM
NM TFT

xmichaeluk
02-18-08, 01:34 PM
EciDemon, you're GOD :) Thank you so much for clarifying all of this to me, I'm now sure what to do.

EciDemon
02-19-08, 02:12 AM
no prob, im supriced you could make something out of that mess lol