Two gtx 660's w/ a gtx470 for physX

Erm... You can technically RUN it, yes... but it's going to be a rather shitty setup.

If you don't already have the 660s, can I beg you to spend that money in a better way? You should NEVER crossfire/sli low end cards like that - it causes way more issues than it's worth, and the performance isn't very good.

Why spend the money on two 660s and a 470 when you could buy a 670 for cheaper that would outperform the three cards, not have any microstuttering, AND would work in every game, instead of having to pray that the game supports SLI?

(Because I mean, look at it this way. A 670 will always work and give great performance. In a game that can use both Physx and SLI, then you're in decent shape with the three card setup, IF you can figure out how to keep them cool. However, in a game that doesn't support those, a 670 still gives you good performance, while a three card setup gives you the performance of... a single 660. Most of the time you'll have two thirds of your graphics horsepower just sitting there doing nothing.)

The 660 gtx's are already purchased, so the question is about the 470's use. Also, your information about sli setups is fairly poorly informed. I've run sli setups for years and most games use it very well. Moreover, many tests run by various consumers indicate the performance boost from 660 sli setups. They outperform a single 670 or 680 with ease: http://lanoc.org/review/video-cards/5953-nvidia-gtx-660...

Microstuttering isn't a problem and if it is for a particular game, Nvidia Inspector easily rectifies the issue; there are countless sli profiles for games out there, and they tweak sli performance for each. I've played scores of games and only two products failed to employ SLI, and those were made by a Russian company, C1, so there's no surprise there. I ran single card setups for years, and I'm far more impressed with tempertures, and gaming performances, i.e., fps, with SLI setups.

Does your motherboard have three PCI Express x16 slots that will operate in x16/x8/x8 mode or similar?

afaik 2 660 should do fine even with physx being enable without the aid of 470. since you got all the cards (2 660, 1 470) you can try it yourself if it's worth it or not. if i were you i might put that 470 in othet pc or just sell it for exra cash.

Agreed. I have a single GTX670 and I will say that for someone who plays games with Physx you DO NOT need a physx card. I play the following games I can turn them up to high physx and still have decent frames. If I were you get the money you can for the 470 while it has worth  

Batman Arkham City
Batman Arkham Asylum
Borderlands 2
Metro 2033

latest nvidia cards are quite capable to run max out game setting with physx set to high and still have decent frame rates. i'm using my 460 with 1600x900 res. in arkham asylum i'm still able to get 50-60fps most of the time with max setting (though i don't remember what my AA levels are) with physx set to high. my performance only drop significantly when playing in the scarecrow level which drop my fps in 20-30 range.

in arkham city using dx11 have much more impact on the performance than physx (it is even worst without the dx11 performance issue patch) enabling dx11 option will imidietely drop my fps to 30 fps even without physx. so in the end i end up using dx9 + physx because the performance impact are much tolarable (40-60fps). plus the effect of physx are much more visible in the game than dx11.

Agreed I'll post a couple of stored pictures I have of Arkham City I do agree that DX11 is more demanding the Physx. I have a 1920x1080p monitor now the frames dropped a little but not very much 2-3 frames here and there.

dont bother with the gtx 470 as a physx, I would say sell it right now since they are not quiet 3 generations behind yet, and they are about $160 on ebay. Grab some cash for something other than a feature that can easily be run on two 660s

yup as mentioned a few times +1 on selling it

Alright, now that's the info. I'm talking about. Thanks so much for all your help, everyone. The extra 470 will likely cut down too much on airflow, and will def. increase temps. I'm thinkin' about selling it, as suggested.

Yea the added heat can not be good for you.

Also less fan noise since the GTX 470 is louder than the GTX 660 (non-Ti).

might be louder then both Sli'd  

Very good point, especially if the 470 is a stock cooler, someone might mistake your computer F-22 Raptor.

Hey who knows if you hop onto it it may fly away  

lol

I'd like to see a new Peanuts cartoon, w/ Snoopy jumping onto a quad-SLI machine instead of his doghouse. He'd fly off on his quad-sli, Sopwith Camel biplane fighter; he would really give the Red Baron the ol' ack-ack.