Widescreen Gaming Forum

EDIT: I've decided to go with AMD, since Asus just revealed their version of the 7970, which has 4 Displayports! No tearing! Thanks for the feedback anyway, couldn't have done it without you guys.

Okay people, please bear with me through this wall of text. English isn't my native language, so do not hesitate to ask questions of something is unclear.

Hi, I am Moose. I am new to multi-monitor gaming, so I was eager to try it out. I went straight for AMD Eyefinity and never thought of Nvidia Surround (yes, I was a fanboy). I've been spending a lot of time here on this forum and did a lot of research. I came to the conclusion that I had to buy an AMD 6950 Flex edition, so I could hook up my three DVI/HDMI monitors without having to worry about screen tearing. However, I came to a halt. The Flex edition cards could no longer be supplied. I had to find a new solution. Again a lot of research and realised I had just two choices in the end. These choices were found by making decisions time-wise and budget-wise. Also, I do not want any screen tearing issues. The following emerged:

1) Wait for an AMD 7-series card to be released with three similar ports (99% chance that's going to be mini-DP's)
Pros:
(Probably) 3GB memory
(Probably) within budget
Strong GPU
Cons:
Spending an extra €100 ($127) for three adapters

2) Buy three Nvidia cards (my motherboard has three PCI-e x16 slots. HOWEVER, one of the PCI-e x16 slots runs in x4 mode)
Pros:
No screen tearing
No extra money for adapters
One display connected to one card
Cons:
I might need a new PSU (the one I use now has 600 watts)

Now, if I choose option 2 (this will most likely happen), I have a few questions:

I can buy three GTX560 1 GB cards for €470 ($598). For three GTX560 2 GB cards I pay exactly €570 ($725)
1) Is it worth spending an extra €100 ($127) to go from 3GB to 6GB? The resolution I'll be playing on will be ~6000 x 1080 (with bezel adjustment)

2) Is it worth to put a third graphics card in the PCI-e x16 @ x4 (source, scroll down to expansion/connectivity) slot?
I've read some articles about this, and some say you will only get like 5% increase. However, since I'm planning to put each display to a different GPU, will it be worth putting in a ~€170 ($216) GPU in it?

The reason I'm asking this is: I'm worried that if one of the three GPU's runs in an x4 slot, one of the monitors might behave different than the others.
3) Is this assumption correct?

There is ofcourse another way out. I could hook up two monitors to the 1st GPU, one monitor to the the 2nd GPU and the third (x4 slot) has no monitors connected.
4) Does this increase/decrease the performance of your setup?


Information you should know about me:
-I know very little about Nvidia cards
-I do not know how well triple/dual SLI scales with Surround

Please take your time reading this and again, do not hesitate to ask any questions what so ever. I am completely relying on your help as experienced Nvidia users.

nVidia's Surround technology doesn't require 3 GPUs. It requires an SLI setup (or a GTX590 or a fancy version of the GTX 580 such as the Galaxy MDT GeForce GTX 580). Basically you can do Surround with 2 cards or even a single card. The 3rd monitor that's connected to the 2nd card isn't at a reduced performance level compared to the other two.

Multi-GPU setups use Alternate Frame Rendering so your idea of having 3 GPUs to drive 3 monitors isn't really how it works. Google it to learn more.

nVidia Surround is definitely a viable option for what you're looking to do. I'll probably end up with Team Green since I want to drive a 3D Surround setup and AMD has no way of running a HD3D Eyefinity projector setup right now.

Mike

nVidia's Surround technology doesn't require 3 GPUs. It requires an SLI setup (or a GTX590 or a fancy version of the GTX 580 such as the Galaxy MDT GeForce GTX 580). Basically you can do Surround with 2 cards or even a single card. The 3rd monitor that's connected to the 2nd card isn't at a reduced performance level compared to the other two.

I know it doesn't require three GPU's, but you need at least two. Let me visualize things.

Pay attention that one slot is x4 mode (question 2)

Can anyone give me some feedback on this?

Other questions are still open ;)

You would do better to get 2x 560 2gb than you would to get 3x 560 1gb.
Trust me when I say that VRAM goes a long way when multi-monitor gaming!

You would do better to get 2x 560 2gb than you would to get 3x 560 1gb.

I now know that GTX560 TI's do not work in triple SLI. Does that also counts for regular GTX560 2GB cards?
If regular GTX560 2GB cards do work in Triple SLI, would it be worth the money considering one of the cards is in an x4 slot?
I mean, I'd be getting 6GB VRAM if Triple SLI works for regular GTX560 2GB cards.


Pay attention that one slot is x4 mode (question 2)

I mean, I'd be getting 6GB VRAM if Triple SLI works for regular GTX560 2GB cards.

Incorrect, the total amount of VRAM you will ever have is the max of the lowest card.
In this case 2gb of vram, not 6gb.

The same data needs to be replicated across all cards, thus you dont extend the total vram by adding another card, think of it as raid 1 where the data is mirrored on all cards not striped like raid 0.

The same data needs to be replicated across all cards, thus you dont extend the total vram by adding another card, think of it as raid 1 where the data is mirrored on all cards not striped like raid 0.

Why did no one ever told me that? I've looked through hunderds of pages about Eyefinity and Surround, NEVER have I stumbled upon this fact. I presume CrossfireX does the same thing.

1) Getting a single GTX560 2GB card for a single monitor is exactly the same as getting three GTX560 2GB cards for three monitors?
And with CrossfireX this works exactly the same?

If this is correct, let's do some theorycrafting. Looking at computing power, I know that SLI nor CrossfireX scales 100% extra per card. Let's make an example.

I've bought three GTX560's. I start Battlefield 3. The two extra cards scale with 0.8. This means I'd get 2.6 times more computing power. 2) Does the 260% percent divide between the three monitors?
If yes, then that means I'd only be getting 87% performance from each card. Is this assumption correct?
If no, (I have no idea what would be happening then).

Please answer these two questions, I am very confused right now :tired:

1) Getting a single GTX560 2GB card for a single monitor is exactly the same as getting three GTX560 2GB cards for three monitors?
And with CrossfireX this works exactly the same?

No

It WOULD be exactly the same if you would run 1920x1080 on each Screen for his own! BUT you're running 5760x1080p! So every GPU calculate one 5760x1080p picture, then the next one does, then the third one does. and then the first starts again.

So if one GTX560 has problems calculating 5760x1080 with 8x AA (not performance wise but Vram!) even if you have 3 GTx560 you won't have any Performace increase at all! Thats what we calla V-ram Limit.
IF you don't have that and the GPU can't calculate fast enough then you get nearly double performance with SLI, or three Times as much in Tri-SLI.

So about Scaling.... well you COULD do a lot of theoretical thinking. But you never know if its true or not... so just go Google and enter "GTX 560 Tri-SLI". I'm sure Hardwareheaven, overcklockers.net or lot other sites have done lot of reviews! And when they Bench GTX560 in SLI or Tri-SLI they normaly also have a single Card for comparission.

I've already worked out that you can't Tri-SLI with GTX 560's. That out of the way, let's ask (yet again) a question.

So if one GTX560 has problems calculating 5760x1080 with 8x AA (not performance wise but Vram!) even if you have 3 GTx560 you won't have any Performace increase at all! Thats what we calla V-ram Limit.
IF you don't have that and the GPU can't calculate fast enough then you get nearly double performance with SLI, or three Times as much in Tri-SLI.

I have two GTX 560 2GB cards installed. I play Battlefield 3 on ~6000*1080. My first card hits the VRAM limit. What exactly will happen next?
1) Will it dump to my system memory?
2) Will the second card pick up where the other left and I can play on without noticing anything?
3) Will the second card say: f*ck it, I'm outta here?

If you hit a VRAM limit your framerate will fall precipitously and it will look like crap. You'd likely need to lower your AA settings to avoid the VRAM limit. The computer won't crash or anything.

I have two GTX 560 2GB cards installed. I play Battlefield 3 on ~6000*1080. My first card hits the VRAM limit. What exactly will happen next?
1) Will it dump to my system memory?
2) Will the second card pick up where the other left and I can play on without noticing anything?
3) Will the second card say: f*ck it, I'm outta here?

None of the above ^ - the game would simply slow.

If you hit a VRAM limit your framerate will fall precipitously and it will look like crap. You'd likely need to lower your AA settings to avoid the VRAM limit. The computer won't crash or anything.

This ^

The pc will be fine, the game just slows.

You know, I got the weirdest thoughts now. Am I correct if I say that if the VRAM limit is reached on one of your cards, the game slows down. And therefor the only thing you *double* or *triple* is the computing power?

Yes, your GPU processing power increases according to the SLI/Crossfire scaling for the game or benchmark you're running. Your VRAM ostensibly remains the same as a single card solution.

I think you're worrying too much about the screen tearing issue. I installed my 7970 last night and could only notice the tearing by moving a window around on the DVI-connected monitor (far left one for me). I played BC2 and BF3 and never noticed any tearing. If you've ever played a game with v-sync disabled you've experienced the screen tearing already.

Thanks for your delightful explanation!

And about the tearing: yes, I might be a bit too worried. The problem is that I've never actually seen the tearing issue with my own eyes. And it's never mentioned in official reviews with 3 monitors. However, I've seen in your system that you use HP ZR24W monitors. I've looked up the specs on those, and you have DVI and DP connections on the monitors. That means you don't have to use any adapters (or a DVI ot HDMI, which doesn't count). I've read from more people that if you don't use DP > DVI adapters you will not get the tearing. So I was wondering how you hooked up your monitors in the first place. Could you be so kind to enlighten me?

Moose

With my old card (5870 Eyefinity6 edition) I just used 3 mini-DP links to connect the 3 monitors. There is a simple passive adapter in-line to convert between mini-DP and DP. They're electrically equivalent. There was no screen tearing with that setup.

My new card, a reference 7970, has only 2 mini-DP, 1 HDMI and a DVI connection. I'm using the 2 mini-DP connectors for the center and right monitors. The DVI connector drives the left monitor. There is screen tearing on the left monitor. I think the tearing is a result of the DVI connection being out-of-sync with frame buffer updates from the video card. The mini-DP links are in-sync and have no tearing.

Thanks for the info. I've already worked out the problems causing tearing, I'm just obsessed with trying not to get the problem myself. It's extra difficult because I've got three DVI/HDMI screens :/

I've always wondered if it'd be annoying or very noticable. I've got two choices left: get two GTX560/570 2GB cards or go for an 7970/6990/GTX590 (the last two are slightly over budget at the moment). However, If I buy an 7970 I have to buy a 30 bucks adapter, and if I buy an 6990 I'd have to buy three adapters (90 bucks).

What would you do if you were me? (also take tearing into consideration)

Moose

7970. Single GPU solutions have less headaches. If the tearing bothers you then get an MST hub this summer and buy 2 more active adapters - problem solved.

You know what? I made myself a new list of choices based on what you said and what I found out (this never ends :tired:)

1) Buy an AMD 6990
With this card I get 2 x DisplayPort-DVI-adapter | 1 x DisplayPort-HDMI adapter.
If I want to eliminate screentearing I have to buy one adapter more, which will result in a total price of 625 euro's.

2) Buy an AMD 7970
With this card I get 2 x DisplayPort - Apple mini-DisplayPort | 1 x HDMI - 19-pens HDMI type A ( met adapter ) | 1 x DVI-I (dubbele verbinding) - 29-pin combined DVI.
I am not sure if I get the right adapters with this card, could anybody tell me if the Apple mini-Displayport adapters are the same as the ones I get with the 6990?
If yes, then this would cost me 510 euro's in total.
However, I would still have screentearing until the MST hub comes out. This means another XXX euro's and an extra adapter. Does an MST hub also increase input lag?

3) Buy two GTX560 2GB cards
With these cards I'd have no tearing and I do not have to buy any adapters. However, SLI does not always work properly.
This will cost me around 400 euro's.

Please give some valid arguments and/or benchmarks so I can make my mind up.
Moose

EDIT: I will also make some argument and look up benchmarks myself, but I cannot speak from experience. That's why I am asking you :)

what do you mean sli does not always work properly?
while its true a number of games didnt have out of the box support i havnt seen recent AAA titles have that issue, or they are repidly patched.

the only headaches i really have from my setup (2x gtx 470s) are the same ones anyone with 3x monitors running a single res have.

why i went with 2x 470s:
i had to really hunt them down as not many places still sell them, but they bench higher than the current 560s and were similarly priced.
i actually care about physX. playing games like batman or Alice without physX would kill me, for me in a game its all about the little things, so i "needed" (lol) that stuff.
i think nvidias drivers (while yes they have issues) are a bit more solid, at least in my experience.. i seriously loathe CCC.


that 7970 looks really kickass on paper and it benches great.
it also would eliminate alot of issues with multiple cards, might be worth it for easier use..


as for tearing on nvidia, i dont get any tearing in games, no tearing on movies and such either. However if i watch a video on a video player that uses hardware accelleration, or i watch a youtube video which also does that, i get tearing on one monitor, but only at high resolutions, and it gets worse the higher the res. at 480p its pretty much not noticable, at 720 its mild, and at 1080 its pretty obvious. the monitor it tears on is one plugged into the second card, and if i switch the ports around one monitor still tears no matter what. of course those resolutions dont really reach the side monitors but if i stretch them or reposition them or whatever is when i see it.

You know what? I made myself a new list of choices based on what you said and what I found out (this never ends :tired:)

1) Buy an AMD 6990
With this card I get 2 x DisplayPort-DVI-adapter | 1 x DisplayPort-HDMI adapter.
If I want to eliminate screentearing I have to buy one adapter more, which will result in a total price of 625 euro's.

2) Buy an AMD 7970
With this card I get 2 x DisplayPort - Apple mini-DisplayPort | 1 x HDMI - 19-pens HDMI type A ( met adapter ) | 1 x DVI-I (dubbele verbinding) - 29-pin combined DVI.
I am not sure if I get the right adapters with this card, could anybody tell me if the Apple mini-Displayport adapters are the same as the ones I get with the 6990?
If yes, then this would cost me 510 euro's in total.
However, I would still have screentearing until the MST hub comes out. This means another XXX euro's and an extra adapter. Does an MST hub also increase input lag?

3) Buy two GTX560 2GB cards
With these cards I'd have no tearing and I do not have to buy any adapters. However, SLI does not always work properly.
This will cost me around 400 euro's.

Please give some valid arguments and/or benchmarks so I can make my mind up.
Moose

EDIT: I will also make some argument and look up benchmarks myself, but I cannot speak from experience. That's why I am asking you :)

I'm going to say exactly the same thing again. Buy a 7970. Multi-GPU setups can be a headache (a 6990 is a multi-GPU card if you didn't know). If you've never noticed the tearing before and you've played a game with v-sync turned off then the tearing won't bother you (it was there but you didn't notice it).

No one knows the details about the upcoming MST hubs - they're not out yet. I'm pretty familiar with the DP 1.2 spec though and it would make no sense for the hub to buffer any of the incoming signal so you shouldn't get any more input lag as a result of the hub.