New Graphics Card For Eyefinity

[Damienyoung]

I am faced with the problem of my new 6870 not being fast enough to support eyefinity gaming on high graphics.

I am yet to receive my monitors and I would go out and purchase a Sapphire/Gigabyte HD 6970; but a certain issue has been brought to my attention. Screen Tearing.

As I understand screen tearing is meant to be due to different frame rates of the DVI ports and the Display ports. Although there has been problems using only DVI in crossfire. Does anyone know if this issue has been fixed with drivers or a way to avoid it that works 100% of the time?

Even nVidia card have this issue, but are fixed easier.

If I got the Sapphire HD 6970 with 2 DVI and on DP -> DVI,
1) Is it 100% likely to screen tear?
2) If it is, would I be able to eliminate the tearing by forcing V-Sync and Triple Buffering?
3) If screen tearing is very likely, can anyone suggest a new Graphics Card? (2gb eyefinity edition, 6990)
4) With the new graphics card, are there any issues I am likely to face?

 

[plznote]

You should CF your 6870.
It would be cheaper and powerful as well.
Performing around the 5970.

 

[Derbixrace]

all i can say is that you want much VRAM for eyefinity, preferrably 2GB per gpu.

 

[Damienyoung]

Tearing and gaming for at least the next 2 years are my biggest worry.

It must run eyefinity on 3 monitors and I dont like the incopatibility of crossfire.

How about this http://www.memoryexpress.com/Products/PID-MX32580(ME).aspx
And run the monitors of Display port adapters to HDMI.
This should eliminate the tearing shouldnt it?

 

[yyk71200]

Tearing is the most evident when framerate is higher than the monitor's refresh rate. In crossfire you get higher FPS therefore you may experience more tearing since framerate goes above the monitor's refresh rate more often. A solution would be to enable VSyncronization so the card marches a rendered frame with refresh of the monitor. It may slowdown framerate quite a bit. If framerate becomes too low, forcing triple buffering may reduce framerate drop. However, it still be no higher than the monitor's refresh rate.

 

[Damienyoung]

Yes, this is what I have heard. And apparently V-sync sometimes makes it lag, hense, triple buffering.

But howcome people with 150+ fps dont get tearing? Or is this all a benchmarking gimmick?

Even though my Sapphire 6970 is 3 weeks old, I wouldnt mind upgrading to a 2gig card for new games. http://www.memoryexpress.com/Produ [...] 0(ME).aspx

Please tell me what you think

 

[Damienyoung]

sorry: http://www.asus.com/product.aspx?P_ID=jX64GujNeYxnA4sd

 

[yyk71200]

1st: Tearing if one of shortcommings of LCD monitors. You don't get it on CRTs.
2nd: Some people are not bothered by tearing and do not report or complain about it (including yours truly).
3rd There are LCD screens that have like 120hz refresh rate. Because of this, they can display high framerate without tearing.

 

[yyk71200]

sorry: http://www.asus.com/product.aspx?P_ID=jX64GujNeYxnA4sd

Nice cooling. Just keep in mind, this one card will take three slots in your PC.

 

[Damienyoung]

So tearing will occur if my game plays at higher fps than the monitors refresh rate, even with that graphics card using the DP's. Because I thought it was caused by the different rates of the DVI and DP's.

120hz are a bit expensive. So if I got that new card and used it with 3 60hz 5ms monitors with v-sync and triple buffering forced, will I have a problem?

Also, I am not sure if I am convinced with the compatibility of eyefinity and whether I should wait for the 7xxx series to be releases

 

[yyk71200]

VSync solves tearing problems. I believe you can get some tearing even when framerate goes under the monitor refresh rate, but it is more rare and less evident. VSync eliminates this problem all together but the frame drop is quite big. For example, if your card displays like 45-50 fps on a 60 Hz monitor, and you enable VSync. the card will wait for monitor to refresh and your fps should drop to around 30. On the other hand, if the graphics card displays more than 60 fps without VSync all the time, your fps with VSync will show 60 fps all the time. Triple buffering reduces frame rate drop if it goes below the monitor's refresh rate because it renders and buffers an additional frame. With v-sync, if fps goes below 60 on 60 hz monitor, you get 30 fps, with tripple buffering, it should go to about 45 fps (if the fps without v-sync below 60 fps but above 45 fps).

 

[Damienyoung]

Ok, so you have nearly convinced me of the cause.

Last questions (you have been incredible helpful)

1) How come the people with that graphics card I linked have said they have no screen tear by using display ports? (is it more common if you use the different cables [DVI and DP]?)

2) What adapters would I need for the display port -> HDMI (does it need to be active? Will any do?)

Thanks in advanced

 

[yyk71200]

I am not a specialist in eyefinity, but for the third monitor you may have to use an active adapter (two monitors I think may get away with a passive, but not three).
About cables, personally, I am not sure but I found this discussion: http://hardforum.com/showthread.php?p=1036966124