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I'm considering SLI - Does microstutter always occur?

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Madpacket

Platinum Member
Nov 15, 2005
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326
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Both AMD and nVIDIA's solutions suffer from microstutter and the problems are exasperated especially in surround gaming mode / eyefinity. I do not recommend either solution and instead suggest going with the fastest single card you can afford and overclocking it. Just make sure you get one with enough VRAM.

Until AFR is replaced with something more elegant this will continue to be a problem.
 

cmdrdredd

Lifer
Dec 12, 2001
26,848
280
126
Both AMD and nVIDIA's solutions suffer from microstutter and the problems are exasperated especially in surround gaming mode / eyefinity. I do not recommend either solution and instead suggest going with the fastest single card you can afford and overclocking it. Just make sure you get one with enough VRAM.

Until AFR is replaced with something more elegant this will continue to be a problem.
Then what do you suggest for someone running a resolution that no single card can run past 30fps at?

There are many reasons and situations where SLI or X-Fire are all you can do to keep performance up.
 

Shmee

Memory and Storage, Graphics Cards
Super Moderator
Sep 13, 2008
5,331
981
126
I would say that both SLI and CF in recent times has become quite good, and I would have no problem recommending it if needed for high res and good quality.

My only issue is that some older games or poorly coded games dont scale well, such as world of tanks.
 

boxleitnerb

Platinum Member
Nov 1, 2011
2,597
1
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You never hear that CF is smoother than SLI. But the other way around you here it quite often from users and reviewers alike. Until AMD addresses their stuttering/smoothness problems, CF cannot be recommended.
 

Lonbjerg

Diamond Member
Dec 6, 2009
4,419
0
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Microstutter is ALWAYS there with multi-GPU (a downside of AFR rendering)...but if you PERCIEVE it...that is another matter entirely....and depends on your fysiology.
 

BrightCandle

Diamond Member
Mar 15, 2007
4,762
0
76
Its certainly there and measurable in both solutions using fraps frame times. Its less problematic under SLI than in CF when comparing the 680 to the 7970. Having experienced both I would choose NVidia, but I would choose single fastest card unless you really need the extra performance (basically triple monitor users).
 

PrincessFrosty

Platinum Member
Feb 13, 2008
2,301
68
91
www.frostyhacks.blogspot.com
Microstutter occurs all the time, in fact it occurs on just a single GPU but just to a much less pronounced degree.

People are sensitive to it in different amounts, generally speaking the higher the frame rate, the harder it is to see. However requiring a higher frame rate to get the same apparent smooth motion is really just mitigating the benefit of multi-GPU solutions. If you add that to the fact that scaling is often not 100% on most games, the value of cost to performance ratio of your 2nd card, goes right down, making it harder to justify.

I've used SLI and Crossfire on both single and dual card configs and it's never been a very good experience for long, typically I'm more worried about game compatibility and visual artefacts than micro-stutter, I did find it more or less a necessity to power my 2560x1600 display but honestly with the recent console generation causing stagnation in games requirements on hardware I've not been pressed to upgrade my GPU since my GTX580.

My advice is shoot for the highest end single GPU solution, the GTX680 is a great performer, there are maybe a grand total of 3 games you wont be able to max in 2560x1600, BF3, The Witcher 2, Metro 2033, that's about it I think...
 
Feb 19, 2009
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You never hear that CF is smoother than SLI. But the other way around you here it quite often from users and reviewers alike. Until AMD addresses their stuttering/smoothness problems, CF cannot be recommended.
So you can't recommend CF due to a subjective problem, even when most ppl do not notice MS?? meh
 

boxleitnerb

Platinum Member
Nov 1, 2011
2,597
1
81
The fact that many people perceive it this way and that it gets mentioned again and again makes it less subjective but more of an established fact. And a first time multi-GPU user will not know if he is sensitive to MS or not. Why take the risk? Rather make the sensible choice right away. I'm sorry, but if you want CF to be recommended, press AMD to work on this issue as Nvidia has been doing for years now.
 

AdamK47

Lifer
Oct 9, 1999
13,591
968
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I always play with vsync on at 60hz and have found that the easiest way to combat micro-sutter is to maintain 60 frames per second. It can be expensive if you want everything maxed though. Small drops in the framerate can cause noticable micro-stutter. There are times when the drivers (AMD in particular) run at 59fps or 61fps and induce micro-stutter even when there should be none. Thankfully, there are utilities that can lock framerates to 60.
 

blackened23

Diamond Member
Jul 26, 2011
8,548
1
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I have seen microstutter on older GPUs, yet on my previous 7970CF setup, there was no MS. Playing on a single screen at 2560 resolution.
 

thestrangebrew1

Diamond Member
Dec 7, 2011
3,204
258
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When I was running SLI'd 7800s I never noticed microstutters. When I had xfired 5770s I would notice micro stutters here and there, but it was never really a performance problem or anything for me. You may notice it, but IMO it shouldn't be a deal breaker. If I had the coin, I'd SLI my 670s in a heartbeat.
 

SirPauly

Diamond Member
Apr 28, 2009
5,187
0
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It may depend on application, subjective tastes and tolerances and frame-rate threshold, what sustained minimum threshold one may be tolerant for -- some it is 60 FPS, 45 FPS, 30 FPS, etc..

Imho,

Where AFR may differ from single GPU's, for me, is the around 30 FPS threshold, where a single GPU may offer smoother sustained minimums than AFR.

However, the positives heavily out weigh the negatives or limitations of multi-GPU at this time. The ability to offer much more performance, while garnering new immersion from settings out of reach with a single GPU.

In the past, one had to wait sometimes years to receive a 50-75 percent jump in performance -- and no matter how much monies one had -- didn't matter -- now, one has at least the choice to add performance and very compelling.

With anything that is GPU related -- there are always trade-offs to consider.
 

Madpacket

Platinum Member
Nov 15, 2005
2,068
326
126
Then what do you suggest for someone running a resolution that no single card can run past 30fps at?

There are many reasons and situations where SLI or X-Fire are all you can do to keep performance up.
Unfortunalty there is no good answer right now. I suggest simply turning down a few settings to get back some FPS. Losing a little image quality is preferable to the stutter that comes with SLI/CFX. A single 7950/7970 or 678/680 is plenty to drive any single monitor today. Heck I'm running a single overclocked 7850 @1225Mhz in an eyefinity setup (5760/1200) and can maintain a comfortable framerate in most games by dialing back some (not many) settings.

As a side, I wonder if/how badly microstutter affects input latency? I'm not sure but it when I was using CFX or SLI it felt more laggy when playing competetive FPS (BF2, BF3).
 

mashumk

Member
May 19, 2012
40
0
0
Does a dual-gpu card process frames like a single-gpu card? Meaning, does it run into the same SLI problems as a true SLI setup since two GPUs are at work? Being on one PCB fixes that?

For Vram issues, the 690 has just 2gb (x2). But one could get two 4gb 670 or 680s and have a higher Vram limit. Of course apparent SLI issues would surface.

Just a case of pick your poison?
 

boxleitnerb

Platinum Member
Nov 1, 2011
2,597
1
81
In my experience, vsync adds much much more input lag than SLI (or CF for that matter). For each additional GPU it is one frame input lag afaik.

I believe if one can maintain 50+fps with SLI, there is very little microstutter involved and it is certainly better than 25-30fps@single GPU.

Edit:
Dual-GPU cards are AFR too. No difference to conventional CF/SLI.
 

moonbogg

Lifer
Jan 8, 2011
10,194
2,022
126
I've had SLI for years and years. I never heard about this until I read people complaining about it. I never noticed it. BF3 on a single 670 with dips in the low 40's feels much more laggy than using SLI and having dips in the 50's.
If my cards microstuter, it is so subtle that I haven't been able to notice, and if i have noticed, then I didn't realize what i was looking at because everything runs smooth as hell.
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
Micro-stutter is only really apparent when using Vsync. It's not like a frame dip, but a slight "glitched" frame feel.

When you're playing competitively with vsync disable, Microstutter can't be seen whatsoever, because, one, you're focused on the game, and two, the screen is tearing the shitznit already...

Micro-stutter is an issue, "if you're looking for it", but in terms of actual gaming experience, it's not that big a hindrance. :D

HOWEVER, to answer your question. YES, microstutter WILL ALWAYS BE THERE, in SLI or crossfire.
Whoa there... micro stutter is a symptom with MANY causes.
It can occur from SLI, from single GPU system being too slow, from CPU being too slow, from being a crappy console port, from improperly coded save mechanism (some games stutter when reaching a checkpoint; which is only due to faulty programming)...

All vsync does to microsttuer is exchange partial frame microstutter (which cause additional tearing) to full frame (as tearing is considered worse) and adaptive vsync doesn't even do that.

And its not a "if you are looking for it". Many people notice it without intentionally looking for it.
Yes, some people can tune it out unless intentionally looking for it. But it doesn't mean everyone who notices and is bothered by it is intentionally looking for it.
 
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serpretetsky

Senior member
Jan 7, 2012
625
19
81
I have been a long time fan of this article
http://techreport.com/discussions.x/21625
which goes into a lot of depth about how frames per second are counted and why this is flawed system

they also have a direct video showing what microstutter is:
http://techreport.com/articles.x/21516

I've personally always been a fan of the way hardocp.com does video card reviews: they try to set the highest settings while still getting perceived smooth gameplay. It's subjective, but it avoids the whole fps issue.
 

PrincessFrosty

Platinum Member
Feb 13, 2008
2,301
68
91
www.frostyhacks.blogspot.com
I have been a long time fan of this article
http://techreport.com/discussions.x/21625
which goes into a lot of depth about how frames per second are counted and why this is flawed system

they also have a direct video showing what microstutter is:
http://techreport.com/articles.x/21516

I've personally always been a fan of the way hardocp.com does video card reviews: they try to set the highest settings while still getting perceived smooth gameplay. It's subjective, but it avoids the whole fps issue.
Except if you don't agree with what is "smooth", then their video card reviews become mostly useless.
 

boxleitnerb

Platinum Member
Nov 1, 2011
2,597
1
81
Well, they can certainly mention if one was smoother than the other. The absolute level of smoothness is subjective, true.
 

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