ATi 4870X2(R700) PCB Debut

[biohead]

aww shucks; avoiding crysis like the plague.


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.

we're not on the same page here. i meant video as in film. PAL is 25 fps, NTSC is 29.97 fps.

btw i have stuck a 4850 in my opty rig and it's twice as fast compared to my previous 3870. crysis runs fun, everything runs just fine. you can run games on a sempron for all i care.

[RedBull78]

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.

Agree. Which is why I only buy one most powerfull video card every 2 years.

[annihilat0r]

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.

I'm not saying they are "completely" useless. There are games where they work perfectly, but threre are A LOT OF games in which the performance numbers you're seeing don't reflect the reality at all.

[Sparky]

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

Yeah pretty sad isn't it

Moon is still virgin.

lol wut

[Hu1kamania]

Great post annihilat0r. I disagree with your opinion that one should not buy SLI, I think it comes down to which games you play. I think that SLI/CF support can be fixed (and in many cases has been) in time as well and that it is going to take work on the part of Nvida/AMD and the game developers to make it happen.

I know that microstuttering with SLI/CF has been a hot topic with you for a while now and you have worked hard at bringing to light its short commings. I commed you for that.

[gojirasan]

Even if the 4870x2 doesn't always offer 1.5x - 1.9x the performance of a single 4870, even a single 4870 gets pretty close to a GTX280. And since it looks like the 4870x2 is going to be around the same street price as a GTX280 it seems like a no brainer to me even if there is no attempt to fix the microstutter problem by going to SFR or something. In games with the microstutter problem or where mult-GPU is not supported you will be a bit slower than a GTX280 but in games with multi-GPU driver support (most new games) and without microstutter you will have nearly twice the performance in some cases. Of course that comparison only works if you are not considering a single 4870. For that analysis we may be talking a $250 street price (by August) for the 4870 vs. a $499 MSRP on the 4870. It's more of a personal thing whether it is worth the extra money in that case.

[flopper]

what if the 4870x2 have some new interesting solution to the microphenomena?
Then its worthwhile.
and will sell like hotcakes.

[Xcel]

thanks for the insight annihilat0r! I sure hope the problem can be solved, the youtube crysis video with tri-sli gtx280s is pretty horrible.

[annihilat0r]

I'll buy one then. Definitely. The only solution to microstuttering is to trying to synch the frames by delaying the frame request from one of the GPUs by some milliseconds according to the general rendering statistics. Which is fine, but can lower FPS significantly in some cases, I believe. I don't care if FPS drops from 75 to 70, but maybe the firms will be unwilling to do it just because it lowers FPS and review sites only show FPS's.

XCel: Thanks. I have full frame-time benchmarks with microstuttering analysis on an Excel sheet. I wonder if I should open a thread and post the results... I'm unwilling to respond to big debates, though. I'm weary about that.

[Aberration]

I just dont understand how something like this can still be happening.

The only problem is the frames from each card are being rendered to close. Obviously it is, but I would just think that this can not be too freaking hard to diagnose and solve.

[ymer]

looks hard to fix... but lets wait for the results

[Shakti]

In a graphic forum some guy is developing a tool to harmonize micro stuttering \ limit the fps. But he just has started, so the outcome is still unsure.

[Eson]

So.. has anyone tried Vsync on? Wouldnt that help?

[trans am]

I've been running crossfire and x3870x2 and never had one problem with microstuttering granted I only play BF2, 2142, unreal3, and cod series and 3dmark

[Hu1kamania]

So.. has anyone tried Vsync on? Wouldnt that help?

Or setting a max frame rate?

[ymer]

I doubt that setting a max framerate would help, the problem is synching the frames..

[Riggs]

I've been running crossfire and x3870x2 and never had one problem with microstuttering granted I only play BF2, 2142, unreal3, and cod series and 3dmark

3Dmarks a game now?

[Hu1kamania]

I doubt that setting a max framerate would help, the problem is synching the frames..

You are probably right...it was just a thought. I figured it would aleviate the rogue 150 fps frame spikes.

I would like to know though it vsync or setting a max frame rate makes a difference...I have seen it mentioned before and not confirmed.

[Sampsa]

Sorry, was busy today finishing 4870/4850 article, I'll test during weekend with 4870, 4870 X2 & 3870 X2 in Crysis and see if I can draw some conclusion about microstuttering.

[zlojack]

That's what I'd like to see ^^

[eric66]

Sorry, was busy today finishing 4870/4850 article, I'll test during weekend with 4870, 4870 X2 & 3870 X2 in Crysis and see if I can draw some conclusion about microstuttering.

be quick everybody is waiting

[annihilat0r]

Sorry, was busy today finishing 4870/4850 article, I'll test during weekend with 4870, 4870 X2 & 3870 X2 in Crysis and see if I can draw some conclusion about microstuttering.

The easiest way; just do a very quick Call of Juarez or Crysis frame-time benchmark in FRAPS and post us the results. Thanks!

[shiznit93]

my stimulus check is burning a whole in the wallet, need to know about microstutter asap . Or the money is going for a downpayment on a CLK320.

[JAG87]

You are probably right...it was just a thought. I figured it would aleviate the rogue 150 fps frame spikes.

I would like to know though it vsync or setting a max frame rate makes a difference...I have seen it mentioned before and not confirmed.

yes my friend, vsync fixes micro stuttering or as I like to call it, jitter. frame capping (@ your refresh rate) also solves it, but it is not by any means a viable solution as you get massive image tearing when your image is running at 60 fps out of sync from your refresh rate (basically with vsync off)

micro stuttering is most evident between 60 and 120 fps (for a 60hz display), where a frame rate of 80 feels more like 40, and a frame rate of 100 feels more like 50. This doesn't happen in all games though (as somebody already mentioned) but holy hell is it ever blatant in the Source engine and in GRID. I dont have any problems in Crysis or COD4 or BF2.

vsync totally fixes the problem in both GRID and Source, but while it is perfectly acceptable in the former, I cannot use vsync in the latter because I dont enjoy getting owned in DOD/TF2.


hope this clears things up.

[Seraphiel]

My experience and take on MGPU scaling and microstutter, and why it isn't a problem for me, but also why I understand it can be for others:

MGPU solutions can scale very well, and the opposite is true as well. It all comes down to the game, settings and resolution. Someone name a game that they have experienced bad SLI scaling with, and if I have it, then I am quite sure I can show the opposite.

Some experience microstutter and some do not. Others have completely misunderstood what it actually is.

I am one those, that either doesn't notice it or never experience it, and that may well be because I always use V-Sync. Look at the numbers below of the exact same scene.