What NVIDIA graphics card should I get
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I think about getting myself a (used) iMac with an NVIDIA graphics card since iray with AMD Radeon graphics cards is a lot slower than 3Delight, plus dForce doesn't work on Macs although they have openCL installed (tested it successfully with a benchmark by intel).
My question is: what NVIDIA graphics card should I get? There are so many out there. Are they all the same for rendering purposes? Here is a list of card I have found in older iMacs (the newer only offer AMD Radeon):
GTX 675MX MD096D/A
GTX 780M 4096
GTX 660M 512MB 820-3298-A
GeForce GTX 660M 512
GeForce GT 640M
Geforce GT 750M
GeForce GT 755M
GeForce GT 775M
680MX A1419
Comments
One thing to check is which family of chip they use (which physicist they are named for) - I suspect at least soem of the 6xx cards are no longer supported, and the 7xx cards are the oldest that will work (I have a 750) and so risk being dropped in the foreseeable future.