well, so far GPUs havent really been able to utilize all the bandwidth with teh 2.0 spec. So x8 2.0 i believe is teh same as x16 1.0.
From what ive heard you might lose a couple frames, no where near enough to worry.

For 2x 480 you're fine with your 850w unit.

For 3 monitors you need SLI. So yes you can do 3 monitors and have 3d. Keep in mind you need 120Hz monitors for 3D. And all of them the same. And last but not least you need the new drivers from Nvidia.

There will be a performance hit due to the resolution and to the 3d that's for sure.

I don't know about TriSLI of 480. Haven't seen a review to tell you if the gains will be worth it.

Also the GTX 480 doesn't take to much of a performance hit when running at x8. See link!

yes, my mother board does support either x16 x16 x1 or x16 x8 x8

I have read a number of reviews comparing x16 vs x8 and the difference is very minimal, almost unnoticable.

oh and by the way thank you for all of the fast responses you guys are great here a forum i went to yesterday for diamond ring for gf no responded for 24 hours it was aggravating so thx (not trying to go off topic just relating speed of members here to other forums replys its great!!)

th3bru1s3r

what i have now...

Asus p6x58d (x16 x16 x1) possible x16 x8 x8 not sure yet gotta look into it but i think it does
core i7 930
6 gb 2000 mhz ram kingston
2x 9800 gtx+
850 watt psu corsair currently going to throw it in another build cuz i think ill need 1000+ for 2 - 3 480s

probably going to buy a corsair 1000w psu if you guys think it can handle 2x 480s

That all looks good, 850W is probably sufficient for 2x480, as Nvidia recommends 600W total system power and additional 250W for another GTX 480.  If you want more headroom to be safe, 1000W would be perfect.

ok so if i get 2 480s:

can i do 3 monitors? and use 3d mode?
if i use 2 monitors will i lose performance?

Yes, you need at least 2 cards in SLI for Nvidia 3D Vision Surround due to a limitation on how many TMDS transmitters are on each physical card.  There's only 2 on each, so you need additional cards to drive more monitors up to 3 so far.  That means 3x1080p displays max in 3D for now.  3D @ 1080p is a limitation of current video formats, as Dual-link DVI can't pass more than 1920x1080x120.  DisplayPort and HDMI 1.4 can handle higher frequency and bandwidth, but there's no true 120Hz displays on the market that currently support this.  If you use 2 monitors and both displays are displaying rendered graphics, then yes you will lose performance, roughly half based on resolution alone.
 
If you game in 3D, that effectively cuts your FPS in half also, so if you were getting 120FPS, in 3D you might see 60FPS.  Gaming in Nvidia surround basically increases GPU requirements 3-fold, so if you have 3x1080p monitors, that's about 3x the GPU power necessary compared to a single 1080p panel, not counting frame buffer (VRAM) considerations. 
 
If you take that further and go 3D Vision, that will again, effectively cut your FPS in half, so 3D Vision Surround on 3x1080p monitors will roughly increase GPU requirements 6-fold compared to a single 1080p monitor.  So yes, the GPU requirements are quite insane really, I personally think it will take at least 2x480 in SLI to run most games reasonably well in 3DVS (3x1080p in 3D) based on my experiences with 2x280 in SLI gaming at 1080p (1x1080p in 3D). 
 
From what I've read/heard from other users, Nvidia is currently supporting 3xSLI in 3D in Beta, and will officially support it later, so if you are looking at 3DVS at 1080p, you may very well want to go with that 3rd card as I'm sure any additional performance will be appreciated at that resolution and setting.  I'm currently looking at 2x470 SLI or 480 SLI just for a single 1080p panel in 3D, it may very well be overkill though, but there are some games where my GTX 280 SLI could use more frames in 3D Vision.
 
Edit: As mentioned by above, 3D Vision requires true 120Hz LCD panels that currently cost $400-$500 each for a 23-24" LCD.  Nvidia Surround (multi-monitor, no 3D) can be a mix of any 60Hz panels at the same resolution.

GPUs: 3x EVGA GTX 480
Monitors: Triple 120 hz
PSU: Silverstone Strider 1500W
Hard Drives: 2x Crucial RealSSD C300 RAID 0

thx helps a lot surprises me that most 120hz stuff will not work... i have a 40 inch samsung led 120hz in my bedroom guess that wont work

so what would the performance increase be percentage wise if you went from 2x 480 @ x16 x16 to 3x 480 @ x16 x8 x8 with one monitor at 1920x1080? not 120hz

chris-nyc
It's really ridiculously confusing and unfortunate, but the nvidia System Requirements page is kept up to date.  If it's not on that page, it's not compatible with 3d Vision.

Amen..  Even the CRT screens have phosphors in them.. Ever hear of ghosting with shutterglasses? It's been a problem for 10+ years and a big reason why 3D vision has never really happened..  CRT monitor makers wanted to have the brightest displays and to do that they put phosphers in the screens that glow long after the first refresh pass.. So the monitor ends up refreshing on top of a glow that existed from the previous refresh and just like that, you've got ghosting..

A lot of the so called "120 Hz" LCD screens do a similar injustice where they're constantly in a phase of blending one frame into the next which totally breaks 3D vision where you're trying to display two very different frames..

There are some exceptions out there, some CRT screens don't have phosphurs in them and some LCDs that really push 120 Hz have not been 3D certified and might work well if you turn off all of the TV's motion processing functions..  But as a general rule, if it's not 3D vision certified, assume it won't work..

I've got 3D vision working on a CRT and the glow from the phosphers prevents me from cranking up the depth..  I can crank up the convergence (pop-out) effect pretty good though without any ghosting..

I plan on buying a Asus 27" 1080p 120 Hz 3D vision certified monitor when they come out this summer..