ATi 4870X2(R700) PCB Debut

[iboomalot]

Do CRTs microshutter???

[ToTTenTranz]

What's a microshutter?

[adamsleath]

not a problem unless your dying to have 1920 4xAA crysis veryhigh...

sorry, not 'multigpu certified'

[Newblar]

when can we expect benches for these things?

[cegras]

Google "crossfire microstutter" or "sli microstutter", you'll get a plethora of results.

Actually, this pretty much scared me away from xfire just now. Poo!

Basically it's when AFR mode is used and the GPU's put on frames asynchronously.

[fellix_bg]

Here is a vivid example of micro-stuttering (honestly, that one actually calls for a "turbo-stuttering").

[Philip_J_Fry]

Here is a vivid example of micro-stuttering (honestly, that one actually calls for a "turbo-stuttering").

yeah ... with all that money spent, $650USD x3 (and is like $499 x3 now).. even @ 40/60+fps, it still stutters

[ymer]

Wow that video looks even worse than the explanations about microstutter that I've read, looks like a poor video card struggling for a few FPS...

[adamsleath]

not fps related then? owell, back to the sync problem...probly gets worse the more cards you try to 'sync.'

[fellix_bg]

FRAPs FPS log can illustrate it quite well, with an Excel graph, but it's pretty much a matter of plain observation.

[awdrifter]

If microstuttering is an AFR problem, why don't they go back to the split frame rendering (sorry, don't know what the technical name for that is)?

[adamsleath]

sfr = screen tearing, and can be slower than afr, although maybe it works now.
wasnt there a chequerboard method? - then you could have 'super-tearing'

whatever method works best for the particular app hey?

afr2 seemed to work best with bf2 and m2tw and tf2 and just about any other game ive played...need for speed (wth sli)

when i tried sfr, my fps were much lower and i got strange artifacts in m2tw.
newer games are probably all just super and have no problems, 'cept crysis; any other apps people know of with multigpu problems?

[generics_user]

LCD's don't refresh like that though. The hertz refresh rate is quite irrelevant.

still explains why i get these stutters in crysis only

[awdrifter]

I guess they should keep both way of rendering then. From the video the tri-SLi GTX280 stutters pretty badly, it might be less annoying to just deal with the tearing in SFR mode.

[biohead]

still explains why i get these stutters in crysis only

do you mean like a constant less-than-smooth feel? or just now and then, when moving into lew areas? because the latter is just the on- and off-loading of textures.

[biohead]

I guess they should keep both way of rendering then. From the video the tri-SLi GTX280 stutters pretty badly, it might be less annoying to just deal with the tearing in SFR mode.

i think not.

there are a number of theories about microstuttering but none are thoroughly put to the test. there aren't any hahrd facts to pin-point the exact problem that's causing it. then there is also a great deal of misunderstanding of what microstuttering implies and i see people labeling pagefiling-symptoms with microstuttering.

as it's all still a big gray arrea, i notice a great deal of people aren't directly talking about the same thing. and to conclude microstuttering from a video is just silly. normal video framerates are between 24 and 30, remember?

[cegras]

still explains why i get these stutters in crysis only

No, the explanation is how everyone else explains it - the graphics cards put out frames asynchronously. There is a prolonged delay for GPU 2 to put it's frame out and it results in a stutter.

[adamsleath]

i see people labeling pagefiling-symptoms with microstuttering.

i dont think so, but if it was how would you fix it? rewrite the game code to access pagefile differently? add more vram to the gtx280

the graphics cards put out frames asynchronously.

i thought this was the 'explanation'

ok when i looked at the video, sure looked like decent fps, but yes i saw the marked stutter or 'sticking' which reminds me of a classic bottleneck 'skipping'

id like to see a video of the same tri gtx 280 at slightly lower settings (ie higher fps) and see the result - i suspect you would still see the skipping / or stutter due to a syncing problem, but im curious to know whether stutter can be eliminated at high fps for example.

i guess there are some 4870 crossfire videos around on youtube somewhere...

http://youtube.com/watch?v=n8I9goSzo50 - wot game is this?

http://www.youtube.com/watch?v=rHfW6J7vHJA - this looked cool

[flopper]

we send ppl to the moon and cant make smooth gameplay?

[Shakti]

Moon is still virgin.

[biohead]

No, the explanation is how everyone else explains it - the graphics cards put out frames asynchronously. There is a prolonged delay for GPU 2 to put it's frame out and it results in a stutter.

instead of producing a constant dung-dung-dung-dung-dung-dung it's more like dung-godung-godung-godung-godung-godung...

lulz.

[adamsleath]

aww shucks; avoiding crysis like the plague.

normal video framerates are between 24 and 30, remember?

not really acceptable.

maybe i should just get a 4850 and stick it with my opty
and get a copy of assassins creed and grid.

[ymer]

It's not just a crysis problem, it has been ongoing since SLI and CF...

[annihilat0r]

Microstuttering makes all multi GPU solutions to date, including 3870x2 and 9800GX2, WORTHLESS.

I did a quite bit research about this, with both my (G92 SLI) and a friend's (9800 Gx2) scores, five games benched.

Assassin's Creed and World in Conflict aren't affected by asynchronous frame rendering (microstutter)
Crysis, Lost Planet and Call of Juarez are ABSOLUTELY affected by asynchronous frame rendering.

I have written a few articles about this which caused some massive uproar and got me banned from several forums. Here are some frame-time benchmark results from Call of Juarez.

Frame number / The time the frame is rendered / How much time it took to render that frame (ms)/ Momentary FPS

48 753 10 103
49 769 16 61
50 784 15 67
51 790 6 174
52 814 24 41
53 832 19 54
54 838 6 178
55 859 21 47
56 877 18 57
57 881 4 235
58 906 25 40
59 921 15 65
60 928 7 142

What FRAPS timedemo would show you: 13 frames rendered in 175ms = 75 FPS

However the real fluidity is much more different than this. You are basically playing at 50-something FPS, with frames rendered at 150FPS being inserted every third frame. Those third frames with super high FPS mean NOTHING for your gaming experience. They do not make your game more fluid. They make micro-stutter. That scene-> you are playing at at most 55 FPS. What the benchies show you is that you are playing at 75 FPS.

This is why you should NEVER, EVER compare single-GPU scores with AFR'ed (SLI/CF) scores. NEVER. And this is also why ALL of the review sites are massively misleading. "A second 8800GT bumped our score from 40FPS to 65FPS!!" REALLY? But you forget to mention that 65 FPS is not comparable with that 40FPS, don't you? It wouldn't matter even if the scenario was like this, would it:

Frame 1 rendered at T = 0ms
Frame 2 rendered at T = 1ms
Frame 3 rendered at T = 40ms
Frame 4 rendered at T = 41ms
Frame 5 rendered at T = 60ms
Frame 6 rendered at T = 61ms

6 frames rendered at 61ms, so 100 FPS huh? Those 20ms gaps where you receive no frames from the cards, and put your real FPS at something like 50 FPS should be ignored because they don't show in the benchmark, and all you care about are the benchmarks.

I'm amazed at after this microstuttering situation broke out how all major review sites are ignoring this and still comparing AFR FPS's to non-AFR FPS's.

DO NOT BUY SLI, DO NOT BUY CROSSFIRE, DO NOT BUY 3870X2, DO NOT BUY 9800GX2, (PROBABLY) DO NOT BUY 4870x2. YOU ARE GAINING ABSOLUTELY NOTHING IN AT LEAST HALF OF ALL GAMES. YOU ARE PAYING TWICE FOR A 1.4X INCREASE IN REAL PERFORMANCE IN HALF OF GAMES. THAT DOES NOT MAKE SENSE.

[Rock&Roll]

Haha. Before you get a bunch of scathing responses to your aggressive declaration of dual-cards being completely useless.....I have to say that I agree with you, based on all the cards preceding the 4870x2. In a few more weeks, We'll know if the 4870x2 stutters or not. If it does, I'm running down to my local micro center and buying a regular 4870....Or I might wait to see what a 1GB 4870 does first before buying.