Nvidia Advice

NVIDIA is better in all ways. NVIDIA and AMD has maybe similar performance, but NVIDIA is higher quality + you get PhysX and 3D Vision.

There's performance comparison between GTX 660 and GTX 660 Ti.

P.S. I'm not a NVIDIA fanboy, but I know something about this. You can have similar performance with AMD cards, but you get higher quality with NVIDIA cards, and as I said, you also get PhysX and 3D Vision.

Btw, you can run PhysX on your CPU.

google it, pls

PhysX isn't that big of a deal.

Again.

You don't need an nVidia card to run PhysX. Instead of being run on the GPU, it'll be run on your CPU if you don't have an nVidia card.

I advise against selling your card merely for PhysX.

AMD is generally cheaper and (save for this generation) better with power and heat. nVidia tends to be pricier, slightly faster, and (save for this generation) hotter and more power hungry.

PhysX sees very little implementation, and getting an nVidia card to accelerate it on your GPU is not worth the price premium in my opinion.

Thanks to everyone for their quick help!

There is no downside to switching from Ati to Nvidia, only upsides.
And the GTX660 Ti is worth it, you know why? Because it's at a much lower price than a 7970, and it's more powerful than it. And it has everything you need, no need to complicate with other silly makeshift enabled PhysX. You'll have true PhysX, something only Nvidia has. Go for the 660 Ti, it's the best gaming video card right now on the market, compared to anything AMD has. No matter how much people lie to themselves, Borderlands 2 PhysX is something for Nvidia only. Just like with Batman Arkham Asylum/City, etc.

Oh yeah, and CUDA cores, 'nuff said.

Those are some overpriced video cards. They should be a lot cheaper than what you are listing as prices. Personally I would get the GTX 670 for $399.

GTX 660ti for $450....where do you live? (I only see them at $299 to $320)

Uh, where do you live? 660's are $230 here and 660ti's are $300. No downside to Nvidia really except that you do pay a bit of a premium, even though the competitor may be ~ the same performance for a bit cheaper. People say generally nvidia drivers are better than AMDs. I haven't had an AMD GPU in years so I can't say personally if this is true. But you're set on moving from AMD to Nvidia. But again I ask where do you live for those outrageous prices?

If you already have a 7850, why not just get yourself a really cheap Nvidia card and use it only for physx? (assuming you have a mobo with 2 pci-e 2.0)

Nvidia is better good move. but no idea which card is better, the first link looked good, or just google it

I have my old Nvidia 9600GSO 384MB and i`m just playing Borderlands 2 everything on Highest @1920x1080 @~40FPS, so the game is not that demanding

Don't waste money! PhysX just has a terrible performance with Medium/High PhysX enabled, no matter if nvidia or AMD...

You can keep your ATI card and add a dedicated nVidia card just for PhysX. http://www.overclock.net/t/1304147/hybrid-ati-nvidia-physx-borderlands-2

If you're spending 450 on a GTX 660Ti You're spending 150 dollars more than its regular price, its about 299 on newegg/amazon.

Physx is fun. All this at a steady 62 frames per second....on a laptop....in bed...with a cheap gtx 580m.

I have an AMD HD6950 2GB and a nVidia 9800GT for PhysX usig this mod: clicky
It should work in Borderlands 2 as well. I confirmed working in Mirror's Edge and Batman 2.
I hope it works with me, BL2 is the reason I bought this extra nVidia card.

BTW, the is a BIG difference between the GTX660 and the GTX660Ti. The GTX660Ti is a full high-end GTX670 GPU with less memory bandwith, de GTX660 is a mainstream GPU.

Well, now that I can play Borderlands 2, I've set everything way up save for PhysX, as the performance hit for playing with it on medium wasn't worth the very little visual fidelity gain.

Vsync on, constant 60fps. HD 7970M - which is a downclocked HD 7870 really.