X1800XT users-Highest refresh rate available for CRT.

[the Chase]

I have a 21" CRT monitor that can do fairly high refresh rates at different resolutions. I'm hoping some X1800XT users can fill me in on the highest refresh rates for the posted resolutions that the cards will support.

Hoping for:
1024 X 768 at 140Hz or more
1152 X 864 at 120Hz
1280 X 960 at 100Hz
1600 X 960 at 85Hz

Can anyone check these resolutions for me? Thanks!

 

[Lonyo]

I think most of those are a given.
My 9800 did 1600x1200 at 85Hz.

It's mostly what the monitor itself can support, not the vid card.

 

[kylebisme]

They are all a given as long as the monitor supports it.

 

[JonnyBlaze]

I used to have a viewsonic pf795. I pushed it with a 9800pro to 160hz @ 800x600. Its all up to the monitor.

 

[kylebisme]

Well it is up to the RAMDAC on the card as well, but modren cards are all plenty capable of the settings mentioned here.

 

[the Chase]

Thanks for the replies! I figured it should be a given-esp. with the X1800XT! But I bought a X800GTO recently and the top refresh rates it lets me do are-

1024 X 768 = 120Hz
1152 X 864 = 100Hz- this one is a bummer for my monitor/situation.
1280 X 960 = 100Hz
1600 X 1200 = 85Hz

So I really want to confirm higher refresh rates are supported by the newer ATI cards before I upgrade again.(I may go X1900XT depending on price/performance and what G71 looks like)!

 

[rbV5]

Ultimately its the RAMDAC speed and driver support that determine the max refresh at a particular resolution for the cards output.

22" Mitsu 2020u CRT X1800XT (Sony GDM-FW900 inf driver)

1024 X 768 = 120Hz verified....won't sync to next setting(150Hz)can select to 200Hz
1152 X 864 = 100Hz-verified....highest driver setting
1280 X 960 = 100Hz-verified...won't sync to the next setting(120Hz)can select to 200Hz
1600 X 1200 = 85Hz-verified...won't sync to next setting(100Hz) can select to 120Hz

My monitor is older, so it simply doesn't support the refresh rates I noted it wouldn't sync to, 2070 Mitsu's can go a little higher, but those are the available driver settings with the latest Catalyst drivers.

You may have some luck with forcing higher settings (1152x864 for instance) with a utility like powerstrip, or perhaps some of the tweaked drivers have modified settings already?

I'm not aware of any card using higher than a 400MHz RAMDAC the Radeon cards use.

 

[JRW]

The chances of your videocard being the limiting factor is pretty much zero ,its your monitor that has the limitations on max refresh rates per resolution.

 

[CP5670]

Just about any modern card uses 400mhz RAMDACs and they should all have the same limits. The monitor will almost always become a limitation before the video card. The nvidia drivers allow you to set up custom resolution/refresh modes, so you can use the intermediate refresh rate values, and I think you can also use powerstrip if the ATI drivers don't already have a similar thing.

 

[JRW]

It is also worth noting that if your monitor supports a wierd max refresh rate such as 98hz you might have to manualy force it in Win XP , For example right now im running 1920x1200 @ 98hz desktop resolution(98hz is listed as max for 1920x in FW900 documention) ,at first using winxp's default refresh rate selection wouldnt let me choose 98hz, only 100hz (which didnt work) ,But I was able to manualy setup 98hz for that res by going into the "Screen resolutions & Refresh rates" option in Nvidia display settings.

 

[rbV5]

Originally posted by: JRW
The chances of your videocard being the limiting factor is pretty much zero ,its your monitor that has the limitations on max refresh rates per resolution.

Actually, the drivers will be the limiting factor if your monitor can support high enough resolutions. You can see with my example higher refresh rates are certainly "possible" given the RAMDAC speed, yet are unavailable in the drivers.

 

[the Chase]

Originally posted by: rbV5

Originally posted by: JRW
The chances of your videocard being the limiting factor is pretty much zero ,its your monitor that has the limitations on max refresh rates per resolution.

Actually, the drivers will be the limiting factor if your monitor can support high enough resolutions. You can see with my example higher refresh rates are certainly "possible" given the RAMDAC speed, yet are unavailable in the drivers.

That's what I was wondering with my X800GTO-is it the drivers or the actual RAMDAC speed thats limiting my refresh rates at these resolutions. I'm not sure what my max. refresh rates for my monitor are(Samsung 1100DF) but I had a 6600GT with this same monitor and it would do-
1024 X 768 at 144Hz
1152 X 864 at 120Hz
1280 X 960 at 100Hz
1600 X 1200 at 85Hz

So I know the monitor can do these and I have installed the drivers for the monitor so I should be OK there.

Thanks for all the tips/replies and I will try the powerstrip idea and maybe hunt around for some modified drivers.(Already tried the newest NGO CAT drivers and no go).

 

[rbV5]

For example 1600x1200@85Hz = 229.5MHz RAMDAC speed Link

 

[the Chase]

Thanks for the read rb V5-pretty interesting-video cards have sure come a long way since 1985! I would think judging from that that it's the drivers that are limiting the refresh rates....Think if I call ATI and ask they would come out with the CAT 6 series earlier and with 1152 X 864 at 120Hz supported??Hmm...

 

[rbV5]

Think if I call ATI and ask they would come out with the CAT 6 series earlier and with 1152 X 864 at 120Hz supported??Hmm...

LOL, thats funny....call them LOL.

You could try powerstrip with the card you have now, there's a trial available. You can edit the registry if you are a glutton for punishment. I recall 1280x960 not even available in the drivers for along time, and then only for 75Hz initially. I was able to use Rage3D tweak way back with the original AIW Radeon to enable it, and run at 85Hz. Perhaps one of the tweakers like ATiTools or Rivatuner would be an option as well...and they're free.

 

[CP5670]

On a side note, I've always wondered why the max refresh rates of a monitor and those of a video card scale differently with the resolution. For example, at 2048x1536 my monitor tops out at 86hz and the video card goes up to 85hz (basically the same thing), while at 1600x1200 the monitor does 110hz but the video card can do 130hz or something like that.

 

[rbV5]

Originally posted by: CP5670
On a side note, I've always wondered why the max refresh rates of a monitor and those of a video card scale differently with the resolution. For example, at 2048x1536 my monitor tops out at 86hz and the video card goes up to 85hz (basically the same thing), while at 1600x1200 the monitor does 110hz but the video card can do 130hz or something like that.

good question, Monitor Bandwidth vs RAMDAC speed?

 

[the Chase]

Would be cool if they had a standard or compatability across the spectrum- will try powerstrip this afternoon- not sure I would want to go with an X1900XT if I can't do the resolutions/rates that I would like- You don't think ATI will take my call on a Sunday??

 

[rbV5]

You don't think ATI will take my call on a Sunday??

Sure, just like any other day

 

[JBT]

why did you get the X1800XT if your going to use 1024x768? or any of those for that matter....

 

[rbV5]

Originally posted by: JBT
why did you get the X1800XT if your going to use 1024x768? or any of those for that matter....

I think he has an X800GTO actually, just wondering about the refresh support.

Generally the higher refreshes allow you to run vsync with higher framerates, or reduce tearing perhaps, and the lower resolutions are again for higher framerates or games that simply don't support higher resolutions. Even an X1800XT will need to have resolution turned down in some games, depending on your host machine and the game itself/settings. (and, yea, I know you know)

 

[the Chase]

Originally posted by: rbV5

You don't think ATI will take my call on a Sunday??

Sure, just like any other day

LOL. Well the powerstrip app. DID work to get me to 120Hz at 1152 X 864!!wOOt! Now got to see if the refresh override will work in say Bf2 where this resolution is still showing up as 100 Hz max.(And try to find out my max. refresh rates for my monitor- maybe I can crank it up even farther!!)

And yep the tearing really seems a lot better(or less worse?) at 120 Hz than at 100Hz esp. when running games with 100fps cap on them. If I were to get the X1900XT hopefully I would have enough horsepower to run bf2 with vsync on and not fall below the 100fps mark with some good eyecandy enabled yet.