CUDA config help

i currently own a gigabyte gtx 480 gpu and i want to go from this to a solid CUDA config for 3ds max,CAD software and other simulation and calculation programs(like f@h and MATLAB),therefore i came up with 2 upgrading solutions:
gtx 480(that i currently have + 1 or more TESLA gpus(max 3)-in fact i thought about the 2070 :)-
gtx 580 as primary card+gtx 480(as psyx card)+1 or 2 TESLAs
the question is in fact if i use a CUDA enabled program(like the iray renderer in 3ds max) will it use the CUDA cores in all of my cards in both configs??(cuz that means that the gtx 480 as phsyx card isn’t a waste cause i primarly do CUDA things so it will be used at all times)

other system spec:
motherboard:asus rampage III extreme
cpu:i7 960
ram:6 gb-1600(i want to upgrade to 12 when i buy the cards)
psu:1000w(i can upgrade that)
case:cm haf 922

please tell me what u think

Take a look at bottom of specifications: A GeForce GTX 480 GPU must be paired with another GeForce GTX 480 GPU (graphics card manufacturer can be different)

I think pairing GTX 480 will work with different card, but only SLI will be disabled. You should check that before buying a new card…

Man i wasn’t talking about sli and apparently you are a bigger newb than i am so ty for your post but it didn’t help :(