Is multi-gpu the way to go now?

[tigersty1e]

when they find a way to finally start using the memory of both cards instead of sharing it, we have taken the next step.

 

[Lonbjerg]

I have the money for a high-end PC so I like to turn the settings up.

You should leave you mom's basement and get a job. Try it sometime.

Uh...touchy.
I left my parents last millenium.
Also went to war last millenium.
I have had a job since I was 13.
My last rig (self build) cost ~$5000

You couldn't make your self look any more stupid if you tried again.

But all this dosn't alter my previous post one bit...just makes you look like a fool.

Come again...

 

[alcoholbob]

Uh...touchy.
I left my parents last millenium.
Also went to war last millenium.
I have had a job since I was 13.
My last rig (self build) cost ~$5000

You couldn't make your self look any more stupid if you tried again.

But all this dosn't alter my previous post one bit...just makes you look like a fool.

Come again...

You are right, responding to a troll who randomly starts attacking people who would never otherwise acknowledge you is definitely foolish of me.

 

[Sylvanas]

The thing with microstuter is you are unlikely to see it first up when you have a new setup with 2 cards that are playing games (presumably) better than before. It's after a while and you get used to it that the rot sets in, and it took me until I actually switched to a single card for me to see it. Huge difference where games 'felt' smoother on a single GPU even though the fps may not be as high.

 

[Keysplayr]

Just report the hell out of him guys/gals. This needs to get addressed. But not here.

 

[BFG10K]

Some very good points have been raised already:

• Micro-stutter and input lag are inherent to AFR.
• Extra points of failure in terms of scaling and general compatibility.
• More heat and noise.

Yes, framerate fluctuations happen on single cards too, but AFR micro-stutter is on top of this. By definition it doesn’t exist on a single card.

Micro-stutter is a lot like AA. It’s only when you lose it that you notice a huge difference.

 

[BFG10K]

Astrallite & Lonbjerg, cut the personal attacks please.

Super Moderator BFG10K.

 

[notty22]

Some very good points have been raised already:

• Micro-stutter and input lag are inherent to AFR.
• Extra points of failure in terms of scaling and general compatibility.
• More heat and noise.

Yes, framerate fluctuations happen on single cards too, but AFR micro-stutter is on top of this. By definition it doesn’t exist on a single card.

Micro-stutter is a lot like AA. It’s only when you lose it that you notice a huge difference.

I disagree with your analogy and also with the one above it, where it was equitable to 'rot'. lol
First off, if you have SLI or crossfire, you can take game A and disable sli and see how it runs , for example with lesser settings. And then enable dual gpu, crank your settings and look for this dreaded 'stutter'. I can see how users with a single card want nothing to do with that word 'stutter'. So now it can't exist with a single gpu ?
This fellow concluded differently, but like many of these experts and users without a dual gpu setup, ymmv to the validity of content.
http://www.computerforum.com/168198-microstutter-quantitative-investigation.html

Analysis
The single GPU 5870 actually has MORE ustutter than the dualGPU 5970. Nearly ~44% of the frames rendered with the single GPU deviated from the local average render time by >70%! The 5970 on the other hand only had ~31% of its frames rendered with a deviation of >70% that of the average render time. To address the possibility that the 5970 has fewer, but larger variances while the 5870 has more smaller variances, the threshold for ustutter was increased to 90% variance and the 5970 had ~7% occurrence while the 5870 had ~11%. This suggests that the 5870 has both more and larger ustutter events than the dual GPU 5970.

This data refutes the myth that multi-GPU systems create ustutter.

edit: I agree that ms can exist , but I also find resistance, to believe that some don't experience it.
frustrating .

IDENTIFYING MICROSTUTTERING
"Microstuttering" is a term used to describe a general inconsistency regarding the time between two frames being displayed, and could be best described as a rapid, noticeable shift between a high frame rate and a low one. In an ideal situation each frame is output at equal or very similar intervals, producing smooth and even gameplay, but this isn't always the case even with a single video processor. Microstuttering is a compound issue caused by an improper frame output synchronization between multiple GPUs and a lack of compensation mechanism to assist in normalizing frame delays. This phenomenon becomes progressively easier to see at low frame rates since there is greater time between frame output, but can reduce the subjective frame rate at higher numbers. As previously mentioned, this problem is found on any multi-GPU scaling system drawing frames that require multiple rendering passes. The use of vertical synchronization (and, if possible, triple buffering) can reduce the prevalence of this to some degree.

http://forums.nvidia.com/index.php?showtopic=158727

 

[alcoholbob]

Astrallite & Lonbjerg, cut the personal attacks please.

Super Moderator BFG10K.

My apologies, I was immature to respond to him.

 

[nvidiaintelftw]

Single GPU systems use less power and have, generally, fewer problems. They also have more predictable performance across games.

also every single GPU setup will have a smoother gameplay then a multi gpu setup. A little thing called microstutter comes into play(ussually. can depend on game and driver) but ussually the multi gpu setup result in lower minimum frame rates which is what we should pay attention to for the smoothest and nicest gaming experience, and a single gpu will do better with that. I went from 2 GTX260 core 216 in sli to one HD5870 and my gaming experience changed night and day. gaming was so much smoother.

 

[alcoholbob]

nvidiaintelftw, it's more fair IMO to compare apples to apples. The question should be, did your SLI GTX260s provide a better gaming experience than a single GTX 260?

 

[bunnyfubbles]

I'm about to swap 2 x GTX470 SLI for a single GTX 580 tomorrow, so we shall see

these are the downsides as I saw them:

1. increased noise - fortunately a good set of headphones can virtually eliminate this problem. A headset with closed design with leather (or leather-like) ear pads can effectively block out the vast majority of noise from even the noisiest rigs.

The sacrifice here is that the absolute best headsets as far as providing superior sound stage for sound positioning in games happen to be mostly open designs that would let such noise in.


2. increased power consumption - encouraged me to swap out my incandescant light bulbs to CFLs to "justify" it


3. increased heat - found out the hard way that a lot of motherboards aren't properly designed for SLI/CF. Having no space between the cards is murder on the card that has to fruitlessly try to suck in air right off the back of another insanely hot video card.

Proper spacing can help, but this means dedicating at least 5 slots strictly to the video card system, leaving very little room for a soundcard, something I highly value. And even though there's almost always a slot left over for a sound card, I no longer have a choice of where to put it, as I'd otherwise place as far away from the other components as possible so as to cut back on interference. Another issue I've had that I have otherwise never experienced before is the heat from my video cards can actually negatively affect my soundcard. Since my soundcard is sandwiched right next to my hottest video card, if I do not keep good airflow over the sound card and do not keep that particular GPU below ~85C I will start to receive artifacts in the audio.


4. increased input lag - as a competitive gamer this would be one of the biggest drawbacks for me, however the input lag inherent in other things such as vsync or the average LCD are worse. Upgrading to a monitor with lower input lag, especially if its a faster monitor such as one of the newer 120Hz LCDs, can effectively eliminate the added input lag due to AFR. Although ideally I'd be on single GPU regardless as long as I can get the insane speeds and qualities I desire from a single GPU. I'm finding more and more that I'd rather just turn settings down, but it is fun to enjoy the luxury of extreme eye candy every now and then.


5. microstutter - maybe I've been lucky to avoid games where this is more of a problem, but it hasn't been too big of an issue. I've also been lucky to avoid it thanks to my adequately fast rig and monitor

However whenever the issue does present itself it is incredibly annoying.


6. other - quirks here and there are annoying, for instance my GPUs never clock down to their lowest power states when in desktop because I run dual monitors.

 

[Lonbjerg]

What does my eye spot?:
http://hardforum.com/showthread.php?p=1036629532#post1036629532

I run 3x 30" on 2x 580's and in most games I can get 60+ FPS with some graphic setting tweaking. You'd be surprised on how much quicker your games can run when turning down settings that a lot of the time don't even hurt image quality. Only problem with 12.3 mega pixels is I do run out of Vram pretty quickly and in some games I can't run any AA and some just 2x AA. But at that super high resolution you don't need much AA to begin with.

So turning down settings even happens on multi-GPU...now ain't that ironic.

 

[SlowSpyder]

What does my eye spot?:
http://hardforum.com/showthread.php?p=1036629532#post1036629532



So turning down settings even happens on multi-GPU...now ain't that ironic.

Well of course. I don't think anyone claimed that having a multi-GPU setup meant that every game, even on three 30" monitors could be played at full eye candy.

Let's pretend that a single GTX580 can drive three 30" monitors (Maybe it can? I think with Nvidia you need multi-GPU to use Surrond). Would you think the gaming experience would be better on a single GTX580 or two GTX580's? Or looking at the same budget, would you think three 30" monitors would be better over a GTX580 or two 6950's?

 

[Lonbjerg]

Well of course. I don't think anyone claimed that having a multi-GPU setup meant that every game, even on three 30" monitors could be played at full eye candy.

Let's pretend that a single GTX580 can drive three 30" monitors (Maybe it can? I think with Nvidia you need multi-GPU to use Surrond). Would you think the gaming experience would be better on a single GTX580 or two GTX580's? Or looking at the same budget, would you think three 30" monitors would be better over a GTX580 or two 6950's?

Depends on if your flavour is consoleports (like most people in here)....or you like PC games.

So far there a a few games that really hurt PC's:
Arma2
Metro 2033
The old Crysis + Warhead.

The rest is either CPU limited (BF2:BC, due to the scripted physics killing performance) og just DX9 type consoleports.

 

[betasub]

So turning down settings even happens on multi-GPU...now ain't that ironic.

Well yeah, particularly because under those conditions you are likely to be vRAM-limited (so adding extra GPUs doesn't gain much).

 

[SirPauly]

Tend to look at Multi-GPU in this context: An ability to enhance the slave core. What does the second GPU do to enhance the single GPU? What are the positives in this context? Then what are the limitations? I believe it is disingenuous to blanket performance and the experience as the same as a single GPU.

 

[Grooveriding]

With the stagnant state of PC gaming and the over abundance of power found in the latest gpus; these days multi-gpu is for very high resolutions and maximum IQ settings with healthy doses of AA.

That or going for single-gpu halo performance on a budget with setups like 6850CF or 460SLI.

There is some incredible performance for your dollar to be had these days with multi-gpu. 6950CF is a truckload of performance for $500. Setups like 460SLI are impressive amounts of performance as well at $350.

 

[kami]

Having used both, I prefer a single card. If you can afford a single card in the Mid-High end range (looking at nvidia's current lineup this is where I'd place the GTX 570) I can't think of a single game that is going to suffer at 1920x1080/1200 on high detail settings, with a handful that may have some problems at 2560x1600.

The extra heat, power, and noise sucks...so does the stutter if you can see it.

But for the biggest and best benchmark numbers? Multi-GPU all the way!

 

[njdevilsfan87]

I ended up going with dual-card this time. The main reason was that I've never done it before, and wanted to give a shot. I went 2x HD6850s over a single GTX 570 or HD6970. I've had them for about a week, and here are my impressions:

Pros
1) They are scaling extremely well. A lot of my games are seeing nearly double the frame rates. I don't seem to notice any major micro-stuttering, but that may be because my frame rates when from around 25-50 to 40-80 depending on the game.
2) They seem just right for 1080p. With a single card, I can run games nearly maxed, but applying large amounts of filtering brings the frames down. With the second card, I can filter away.
3) Power load isn't as much as I expected. I have a 850HX so I could have probably gone with 6950s if I wanted to, but that was outside of my desired budget. I pull around 360W from the wall during RIFT. What is impressive about that figure to me is that it's comparable to a highly overclocked Q6600 + single G92 GTS system I had 3 years ago. (Slightly more, the old system maybe pulled 320W under game load)

Cons
1) The run very hot together. The single card ran at maybe 75C in games. The two of them together run at 88C and 95C. It doesn't help that the one which runs hotter has a sound card right on top of it. Opening up the side panel and just sensing with my hand the heat in the vicinity of the two video cards... I've never felt so much heat being exhaust from a computer! Well, if they break, that's why I bought XFX. I personally never really cared for part temperatures as long as they were backed by a good warranty.
2) Can't achieve as high an overclock as with single. Both cards run 850/1125 no problem by themselves, but it sees like in crossfire I'm more limited to 825/1100. I'm guessing that is due to the temperature differences between the setups.
3) Noisy! So I'll admit, the XFX HD6850s I bought didn't really look like they were meant to be ran in crossfire. The fans don't exhaust heat out the back, so I had to setup this exhaust helper fan. These things get loud. Thankfully my P182 absorbs some of the noise. But still... it's loud. But nothing a slight increase of the volume on the computer speakers doesn't fix.


Overall
I'm highly impressed. Hopefully these two cards will be able to run Skyrim and BF3 extremely well. I am not regretting the decision one bit right now. If prices and performance of mid-range versus high-end cards remain as they are right now, I may just continue the dual-gpu route, unless I need the extra slots.

 

[DrBoss]

With the stagnant state of PC gaming and the over abundance of power found in the latest gpus; these days multi-gpu is for very high resolutions and maximum IQ settings with healthy doses of AA.

That or going for single-gpu halo performance on a budget with setups like 6850CF or 460SLI.

There is some incredible performance for your dollar to be had these days with multi-gpu. 6950CF is a truckload of performance for $500. Setups like 460SLI are impressive amounts of performance as well at $350.

Agreed.

With the 6950CF setup, you can also disable one of the card for less demanding games. Best of both worlds? Brute power (Crossfire) when you need it, high performance single card (CF disabled) when you don't.

So for these garbage console ports that keep coming out, you can simply bypass the "micro-stutter" issue (if its a problem for you) by disabling the second card.

 

[DrBoss]

Depends on if your flavour is consoleports (like most people in here)....or you like PC games.

Are you saying you prefer console ports?

I don't think "most people" on these forums like the direction (toward console ports) that the PC gaming market is headed.

 

[bryanW1995]

I've owned 3 Crossfire setups since it's inception and the scaling was never an issue for me. If you stuck to high profile games (like I did) there was no issue. When using a Multi-GPU I found I got used to the microstuttering and after a while didn't notice it. It was only until I swapped out my Multi-GPU setup for a powerful single GPU solution that I saw the difference was night and day - since then, I will never go back to Multi-GPU while it still uses AFR. Theres no other way to say it but in retrospect it was a sub par gaming experience on multi.

IMO Fastest single GPU > Multi-GPU

what was your last xfire setup? what was the single gpu that you switched to that showed you how bad the microstuttering was?