The State of Smoothness and Frametimes
Before we dive into the questions above, there is one topic that has been burning on our minds to talk about since we've been testing a lot of SLI and CrossFire lately. We need to discuss where we are in terms of SLI and CrossFire smoothness and frametimes. That old issue about choppy or stuttering gameplay under SLI and CrossFire which we have been addressing subjectively for many years now.
In the past it was commonplace to complain about stuttering or choppiness with any AMD CrossFire solution. Times have changed, and we actually find that the roles have now reversed, at least at 4K. AMD has introduced its frametime averaging technology and is fully implemented on AMD R9 290X. AMD R9 290X also introduced new CrossFire technology that does not require a bridge atop the video card and improves communication through the PCI-Express bus. These improvements have proven to be successful in reducing the awful stuttering AMD used to be known for with CrossFire.
In all of our gaming we have shown you today, in every single game AMD CrossFire feels smoother to us than NVIDIA SLI. That's right, the tables have turned on this issue. In fact we experienced many situations where there was choppiness or stuttering with the two ASUS STRIX cards in SLI. It was noticeable, and when we switched to AMD R9 290X CrossFire; CrossFire just felt smoother.
One example of this is in Crysis 3. When we ran 4X MSAA at 3840x2160 with "High" settings we had a smooth experience with ASUS R9 290X CrossFire. However, with ASUS STRIX 780 6GB SLI we had a definite stutter, non-smooth experience despite what the framerates read and despite having 6GB of VRAM. This is a case where the framerates were reading what looked to be playable, at times in the 40's of FPS yet the actual gameplay felt choppy, like it was under 30 FPS! This is exactly the type of phenomenon we used to experience with AMD CrossFire.
Another example of this also happened in Far Cry 3 even running at just 2X MSAA "Ultra" settings. Our experience was altogether smoother with AMD CrossFire. It was as if the numbers we were seeing in FRAPS wasn't matching what we actually felt in game with SLI and this is exactly the way it use to be with AMD CrossFire.
Yet another example is the actual frametime results we have from BF4. Since we are now running that game under Mantle on AMD cards we have to use its built in frame time recorder and from that derive the average framerate. This displays to us the actual frametimes of the game. We often find that the AMD CrossFire frametimes are less than (better) than the NVIDIA SLI frametimes in the game. Granted we are using Mantle on AMD cards, but we have seen that to be true.
Today we can confidently state that AMD CrossFire is going to give you the better gameplay experience than SLI at 4K.
2x GTX 780 ti Strix vs 2x R9 290X DCII.
typo there as its not the ti.
If anything, it clearly shows (and reinforces early reviews of this cooler) how awful the ASUS DC2 R290/X is, crap cooler that's meant for the larger GK110 die (contact area/heatpipes) so it loses efficiency on Hawaii.
Near max fan speed just to prevent throttling with a weak OC, really pathetic.
Not a surprise at all. HardOCP, Sweclockers, Toms Hardware reported a while back that AMD's 290Xs provide better gaming experience in 4K than even 780TI SLI. 780 SLI had no chance of winning.
Let's not forget that they are using 780 6GB too. Had they used 780 3GB SLI, it would have gotten real ugly at 4K:
http://m.hardocp.com/article/2014/0...0_oc_6gb_sli_video_card_review/3#.U9Cp4YkazCQ
Of course from all the CF bashing on our forums, which must be true we all know SLI is better for the last 100 years, right ???? ....
That's why I've been recommending after-market 290s over a single 780Ti for a long time now. People keep buying Nv because of the brand. Hopefully those who read reviews like this one become more informed.
Luckily for NV, 4K is just taking off which means by the time many of us are gaming in 4K, not many will remember that a $650 790Ti couldn't outperform a $350 290 or a $470 290X.
No horse in this race, but have the Xfire improvements now make SLI stutter more noticeable by comparison, or has SLI smoothness regressed?
From my understanding, SLI smoothness itself hasn't regressed, but then 4k is pretty new/demanding, so SLI may not be as smooth as at other resolutions. So it may be partly that, and partly the major Crossfire improvements on the Hawaii cards.
No horse in this race, but have the Xfire improvements now make SLI stutter more noticeable by comparison, or has SLI smoothness regressed?
Nvidia's Sli Bridge might finally be showing its age with 4K. AMD's bridge could only do 1600p.
The thing that helps AMD the most is the much greater bandwidth Pcie 3.0 x16 gives them to move the frames with lower latency. The old link was something like 800MB/s IIRC.
I wouldn't be surprised to see Nvidia move to a similar multi-card technology soon.
I think that's what NVLink is for, expected to launch along with with Pascal in 2016:
http://nvidianews.nvidia.com/News/N...ng-Pave-the-Way-to-Exascale-Computin-ad6.aspx
We can't rule out that this gen NV is struggling at 4K also because of 3GB of VRAM and lower than optimal ROP performance. They should have allowed AIBs to launch 6GB versions of 780Ti. These 2 aspects should be fixed with GM200/210.
Perhaps NV estimated that 4K gaming isn't going to take off until 2016-2017 due to lack of many 4K panels at reasonable prices and slow market adoption. We can even see this on how NV vs. AMD marketed this generation of cards. NV hardly marketed them for 4K gaming (besides Titan Z). Long term their NVLink solution may be better than PCIe but by how much will motherboard prices rise? If NV link allows for 4-5 GPUs to scale well, then it will be a huge breakthrough for PC graphics.
These are 6gig 780's.
He said the Ti models.
And i agreee, the Ti's are awesome cards just need more vram be able to push them (specially via SLI for high rez stuff).
We can't rule out that this gen NV is struggling at 4K also because of 3GB of VRAM and lower than optimal ROP performance.
Could just be nVidia is still struggling with their drivers on 4K. They have had issues with 4K.
If anything, it clearly shows (and reinforces early reviews of this cooler) how awful the ASUS DC2 R290/X is, crap cooler that's meant for the larger GK110 die (contact area/heatpipes) so it loses efficiency on Hawaii.
Near max fan speed just to prevent throttling with a weak OC, really pathetic.