Widescreen Gaming Forum

Even at 5760x1200, 2GB cards run out of RAM in some games. Without anti-aliasing

In some games?, yes, but not in many. Most console ports barely exceeds 700MB at 7680x1600 0xAA. Having 1.5GB should be more than enough for most games. Some games are very vram hungry (GTA4, and in minor scale STALKER, FC2), but only a few.

3 x 24" on 3 x GTX 480, each monitor connected to one GPU

Ideal solution is not three way SLI, because of way SLI works. Two way SLI is more efficient (because this is really a software based surround), and of course monogpu is way more (but only could use two outputs, so minimum is two gpus). With three GPUs you still have to centralize all frames, and then redistribute all of them. With 3x480 it should be faster to use two outputs of one GPU, one output of other GPU, and last GPU with no outputs used, because the optimizations in frame split can be done in the gpu with two outputs used (like with softth), saving PCIE bandwidth when sending splitted frame from GPU1 to output1/output2 (in one simple and very fast step) insted sending to output1/gpu1 and output1/gpu2 through pcie.

With 3x480 it should be faster to use two outputs of one GPU, one output of other GPU, and last GPU with no outputs used, because the optimizations in frame split can be done in the gpu with two outputs used (like with softth), saving PCIE bandwidth when sending splitted frame from GPU1 to output1/output2 (in one simple and very fast step) insted sending to output1/gpu1 and output1/gpu2 through pcie.

Interesting point, do you have 3 x GTX 480 and are you a NV Surround user ?

i want to try tri-sli 480 now :-D

when going 3d surround it drops frames in half. some games cant hang with quad sli gtx 295 :/

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Current Config:

GTX 680 4GB in SLI
Intel 980 x @ 4Ghz

As Surround and Eyefinity is just one big desktop -> quadro's are using this to create big workspaces with multiple cards. Don't know if they are best for playing games tho. Same as with the Firepro's these are good in 3D calculation instead of the slide-show generators what normal "game" cards are :lol:

Eh, I don't see what's different, aside from the fact that Quadro/FirePro drivers are coded for stability first, rather than raw performance. The physical hardware is the same, although the GPUs might be cherry picked and card clocks a little more conservative. :)

[quote] With 3x480 it should be faster to use two outputs of one GPU, one output of other GPU, and last GPU with no outputs used, because the optimizations in frame split can be done in the gpu with two outputs used (like with softth), saving PCIE bandwidth when sending splitted frame from GPU1 to output1/output2 (in one simple and very fast step) insted sending to output1/gpu1 and output1/gpu2 through pcie.

Interesting point, do you have 3 x GTX 480 and are you a NV Surround user ?
I'd be very interested to know whether this had any effect on framerate myself!

Tri-GTX480 users, crack open those benching programs! ;)

Interesting point, do you have 3 x GTX 480 and are you a NV Surround user ?

I must rectify my previous statement. I think there is no difference in tri-sli between using 2-outputs for one card and using one output for each card. The bandwidth used through pcie should be the same.

I have 3x30" with a 285gtx + 8800u / th2go, depending of resolution. Upgrading soon to 2x480GTX. http://www.widescreengamingforum.com/forum/viewtopic.php?f=58&t=16184

I don´t think tri-sli scales well against a dual-sli configuration, mainly because tri-sli will have more bandwith consumption, and both NvidiaSurround/SoftTh are software based solutions for surround using more than one card.

The real difference would be when using two cards against using three cards. With two cards you only need to send 1/3 of the total image to the other card. With three cards you always need to send 2/3 of the total image to the other cards. With lower resolutions that shouldn´t be a problem, but at extreme resolutions, the used pcie bandwidth is really an issue of importance.

Following on from that, I'd be very interested, given that TechPowerUp! has shown that PCI-E bandwidth has almost no impact on fps even with GTX480s until you cut bandwidth down to PCI-E 1x... how much of an impact reduced PCI-E bandwidth has on Surround.

Hm.

If there is an easy way of turning down the PCI-E bandwidth on my UD5, I might give that a shot myself. To the BIOS I go...

Following on from that, I'd be very interested, given that TechPowerUp! has shown that PCI-E bandwidth has almost no impact on fps even with GTX480s until you cut bandwidth down to PCI-E 1x... how much of an impact reduced PCI-E bandwidth has on Surround.

I agree with the low importance in general of PCI-E even with high end graphic cards, but:
- In multigpu PCIE bandwith do have a bigger role (as so the CPU) than with monogpun
- As seen with SoftTh (and Nvidia's is very similar, except for optimizations done at driver level) in very high resolutions, when you have to pass constantly data (apart from the SLI/CF one needed to gpu synchronization), pcie bandwidth is very important.
Because of that, SoftTh has many options to reduce PCIE bandwidth needed (lower resolution in lateral monitor, lower bit depth). You can even test the impact from pcie bandwidth in real time, activating/deactivating lateral outputs with a hotkey (image is rendered always internally at full resolution / full bit depth), so yo can compare results w/wo sending images to lateral monitors, and the differences are about a 30-60% less performance at 3x2560x1600.

The question is how well can manage nvidia drivers all of this. It should be perform far better than SoftTh, but I'm not so sure it fully eliminates the bandwith issue when we are speaking about 12mpx+ resolutions.

After nearly a year of registry hacks, driver issues, driver mods (TwL drivers), performance issues and displayport issues, I sold my dual 5970s and 3x30" and went green. Too many people who had similar rigs I felt were being neglected.

Key points I noticed were:

1. Installation and setup were a breeze. Partly because I had some experience with Eyefinity, but in general, NV Surround seems more polished.

2. Performance-All I can say is that NVIDIA trounces Eyefinity.

HAWX Max settings @ 8080x1440 375 FPS Max, 75 AVE,
Dirt2 Max settings @ 8080x1440 76 FPS AVE, 31 FPS MIN (Post Processing Medium),
WIC Max Settings @ 2560x1440 230 FPS MAX, 85 FPS AVE, 16 FPS MIN.

Min FPS is all important IMO. Little/no microstuttering and games run seemlessly.

3. Setting up displays was a little troublesome. In games that don't run/look better @2560x1440, I had trouble setting up the display so it would run on the center display. Alot of headscratching and musical DVI port swapping, I finally got it working.

4. There is no "grid" feature to manage window resizing/multiple windows (aka ATI Hydragrid). I really liked this feature as I could have 3 windows open simultaneously with each set to a designated display.

5. The extra VRAM on GTX480 makes a difference in performance.

In conclusion, I will NEVER use ATI hardware again. I even swapped my 3870 on my media rig for a GTX250.

Great hardware, Shite software. A shame really.

NVIDIA drivers has it's own share of issues, however, the drivers are more polished.

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Asus Maximus IV Extreme-Z : i7 2600K @ 4.6 : G Skill DDR3 12800 RipJaws 16Gb : 2 x Vertex 3 120Gb : 4 x Seagate Barracuda XT 2Tb : Galaxy GTX 480 Tri SLI : SilverStone Stider ST1500 : Corsair Obsidian 800D : 3 x Dell U2711 : Windows 7 Ultimate x64 : Koolance WC CPU/GPU

@hunuok: Have you run into any bottlenecks only having 1GB of VRAM total?

I'm considering a similar setup, I want to run 3x30"rs. The reason I haven't sold my 5870 is because it has 2GB of VRAM and I like anti-aliasing.

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System Core: | Intel Core i5-2500K + ASUS P8Z68-V + 16GB Corsair XMS3 DDR3 1333 MHz | Win7 x64 | MSI R7970 Lightning 3GB [1105/1400] |
Display: | 3 x Dell Ultrasharp 3007WFP-HC @ 7680x1600 | Dell u3011 |