5x clients 3x video cards 3x monitors... poor performance...

So I decided to go out and upgrade from my 15" monitor that was displaying 4 clients (19" being my main) which all ran from a 8800GTS 640MB card.. I ran around 30-50fps on main and of course 14fps on my other clients (keyclone setting)

What I can't figure out for the life of me is why with more video cards my main runs now at 14fps or less.. same with clients.. What I am trying to setup up is that I can have my main card run my main window at full detail, while the two cheaper cards each run two clients at low settings.. atm every client is set to low ive installed latest motherboard drivers and latest video card drivers as of Jan 8th. Any pointers would be great! My only guess is that all the cards run at the speed of the slowest card? I thought that was just if I had it in SLI mode...

Setup
------------------------------------------------------------
8800GTS (pci-e slot 1) ------> Monitor 1 (client 1)
8500GT(1) pci-e slot 3)( -------> Monitor 2 (client 3, client 5)
8500GT(2) pci-e slot 2) -------> Monitor 3 (client 2, client 4)





Specs
----------------------------------------------
Q6600 2.4Ghz O/C 3.15Ghz
Nforce 780i (Triple SLI)
1x 8800GTS 640MB
2x 8500GTS 512MB
3x 19" Wide Screen (two rotated) H Shape setup
WD-SHTY 200GB HD

My guess is that your bottle neck is the PCIe bus? Too much graphics data trying to get through at the same time.

From what I have always understood the more video cards you use with wow the more your performance will decrease. Thats why I run a single gtx 280. I think the reasoning is that no matter how many cards you have each wow client is rendered to the primary cards hardware first then divided out from there.

I believe it has to do with DirectX assuming the 1st GPU when the target program does not specify which card to use. People put multiple graphics cards in their machines, and assume that they can crank it up now, and they see the decrease in performance because they are basically still running everything on the original card, but with the setings turned up more.

On my mac, WoW runs OpenGL instead of DirectX. I originally started with 2x 30" screens on a single 8800GT. I decided to add a second 8800GT and run 1 30" per graphics card. I expected to see a huge jump in FPS, and i did not. What it did allow me to do is expand up to 4 monitors. I know my machine is fast enough (8 cores, with maybe 50% use in peak condition), i have enough ram (peak usage is at 6 - 8gigs, and i have double that). Its not HDD lag (i have zero pagein/outs occuring, and zero HDD access during laggy conditions)

I'm basically left to believe the previous posters, that its with the way the games (OR video drivers) are being programmed that are not taking advatage of the computational power of the second/third/fourth video GPU's, and are basically just using them for output ports to the monitor. Like "Nitro" explained.

OR

The motherboard on our machines cant pipe that much information to multiple graphics cards. The "highway of information" is only so many lanes wide, and there is too much traffic. Just like "Oswyn" mentioned. I know my machine as both graphics slots running at 16x, but alot of motherboards out there will only run 1 slot at 16x, and then 1 at 8x, and drop the rest to 4x or 2x or (eeeek) 1x speed.

OR

May a little of both.

My observations/experiments says, just like "Nitro" did, and that is to get the "Single" Biggest, Badass, Sick you tounge in a lightsocket power gobbling graphics card you can. Unless your game is specifically designed/optimised to use Xfire/SLI (and if you can get drivers that allow multiple monitors while doing that). Then get your 2 monitors as big as you need to run your Wow clients, then a "whatever" gfx card to run simple 2d stuff like web browsing stuff that will actually get piped to that second card.



-Ray

OS? RAM?

Each extra videocard is another large chunk of memory and processor overhead your computer must now handle. If you're using XP over Vista, that may be part of the problem too.