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Force refresh rate on LCD

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RAA

Member
Joined
Sep 30, 2005
I have a mate who's interested in setting custom refresh rates so that it's possible to 'pick' the frame rate to run at depending on different titles.

It's a Samsung syncmaster 930bf but I was wondering if anyone has tried forcing a custom refresh rate on a LCD using Powerstrip.

I do it with my CRT np, can pick any refresh rate from 50hz upwards. I'm not sure what protection measures are in place for LCD, on my CRT it gives 'Out of sync range' then reverts back to what it was or if it happens using powerstrip there's a hotkey to reset it.

Ideally I would like to start from 50hz, if I can set 50hz for a certain resolution that would be great. Then it's possible to be very specific about what frame cap I want.. that's the reason.

So please say if you've attempted to force a different refresh rate to the ones already available, and if you think it could potentially damage the LCD in any way.

At a guess I would think it's fine cause there's no actual bulb that's 'flickering' it's a sort of artificial refresh rate which had to be incorporated because GFX cards vsync with a monitor by matching the refresh rates. Funny thing is though, why aren't LCD's made with lots of different refresh rates to choose from i.e anything from 40 - 160 for example?
 
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if you are using DVI the monitor will always use 60hz refresh rate as it is a digital signal and will deliver a perfect picture. It isn't the same thing that where 60hz on a CRT kills your eyes from being so bright and contantly refreshing as a LCD refreshes on a per-pixel basis and not the entire screen.

To put it shortly: refresh rate is not directly used by LCDs. If you want to limit your fps to 50, then set it that way in a game if you so desired, if you want more, turn off vsync in your video card properties and have it run as high as you want.
 
This game doesn't have frame cap, besides refresh rate and triple buffer is best way to cap frames.

Darn, so does an LCD still gives tears due to frame rate and refresh rate being out of sync when vsync is off?

I've never had LCD.. what do you think would happen if refresh was set to say 50hz with Powerstrip? Well it would either work or kill the monitor or some kind of protection system activated.

I'll go over to EnTech forums and find out.. :)
 
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i just don't think it would even do anything and continue to display at 60hz (if you are on dvi) I believe VGA allows changing of refresh rates, but I am not sure if it actually changes or just says that it is changed.
 
Agh..

My mate says when he unticks 'Hides modes that this monitor cannot display', it gives 60hz and 75hz. Not sure if they actually work, only way to know is enabling vsync.
 
I have a 19" LCD that supports up to 75hz refresh rate and is connected with DVI. When I play Counter-Strike 1.6 I get 100fps constantly with vsync disabled.

If I have the refresh rate at 60hz I get very noticable tearing. If I have the refresh rate at 75hz I get less tearing. If I set fps_max to 75 then I get zero tearing with 75hz, and a little tearing at 60hz. So the refresh rate does have an impact even when using DVI.
 
I'm kind of scepticle Dermen, I think somethings going on with vsync and not the DVI and LCD. It just doesn't make sense based upon how DVI and LCD's work.
 
ajrettke said:
I'm kind of scepticle Dermen, I think somethings going on with vsync and not the DVI and LCD. It just doesn't make sense based upon how DVI and LCD's work.

Its possible its just in my head that 75hz tears less than 60hz when I am getting 100fps. I really didn't spend a lot of time comparing. I started with it at 60hz then tried 75hz and thought it was better so I stuck with 75hz. I'll look at it again later.

However, 75hz does get me 75 tear free fps and 60hz will only get my 60 tear free fps. I was hoping it would be like my CRT where I could get a little higher fps than my refresh rate without noticable tearing. With my LCD raising the fps just 5 higher than the refresh rate causes noticable tearing. On my CRT I had my fps 15 higher than my refresh rate with no noticable tearing.

***EDIT***
I did some testing and I still think that 75hz does give me slightly less tearing than 60hz when playing CS 1.6 at 100fps with vsync disabled.

The only time when the tearing is bad in CS is when I strafe while an object is close in front of me. I see what I like to call 'tearing lines' They are horizontal lines where the pixels are all messed up looking, kind of like the fuzzy stuff they put over people's faces on TV sometimes.

To test I moved from side to side right up against a box in CS. I would then alt tab and change the refresh rate. With 75hz I can see 4 tearing lines, with 60hz I see 5.

The 2nd test was similar to the 1st. I started at 75hz and ran side to side in front of a box, but instead of being right against the box I was just far enough away that I only saw one tearing line. I then alt tabed and changed the refresh rate to 60hz. When I maximized the game and ran side from side in the same spot I saw 2-3 tearing lines.
 
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With my 7" widescreen carpc LCD to use the native res I have to force 61hz, instead of stock 60hz. So it is possible to force a different res.
 
Agh good..

You know if you don't want to see these tears you can use ATI Tray Tools to force triple buffer on any .exe .. then enable vsync and it'll run great. I use triple buffer in everything. The higher refresh rate will probably work better with it. It's done in 'additional' options when managing profiles. Not sure if it will work for CS cause it's started via steam.
 
Dermen said:
Its possible its just in my head that 75hz tears less than 60hz when I am getting 100fps. I really didn't spend a lot of time comparing. I started with it at 60hz then tried 75hz and thought it was better so I stuck with 75hz. I'll look at it again later.

However, 75hz does get me 75 tear free fps and 60hz will only get my 60 tear free fps. I was hoping it would be like my CRT where I could get a little higher fps than my refresh rate without noticable tearing. With my LCD raising the fps just 5 higher than the refresh rate causes noticable tearing. On my CRT I had my fps 15 higher than my refresh rate with no noticable tearing.

***EDIT***
I did some testing and I still think that 75hz does give me slightly less tearing than 60hz when playing CS 1.6 at 100fps with vsync disabled.

The only time when the tearing is bad in CS is when I strafe while an object is close in front of me. I see what I like to call 'tearing lines' They are horizontal lines where the pixels are all messed up looking, kind of like the fuzzy stuff they put over people's faces on TV sometimes.

To test I moved from side to side right up against a box in CS. I would then alt tab and change the refresh rate. With 75hz I can see 4 tearing lines, with 60hz I see 5.

The 2nd test was similar to the 1st. I started at 75hz and ran side to side in front of a box, but instead of being right against the box I was just far enough away that I only saw one tearing line. I then alt tabed and changed the refresh rate to 60hz. When I maximized the game and ran side from side in the same spot I saw 2-3 tearing lines.
that only makes sense with v-sync disabled to see less tearing when you have a refresh rate closer to the max_fps you have it set to be. But in reality, playing at 60hz with v-sync on should look no different than playing at 75hz with vsync on. you may not be maxing out your card getting 150 (or in my case 300fps in CS:S) but it is a perfect picture and displays that way with it on.
 
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