It is not completely true that nVidia card will not work, but it is true that nVidia cards without support of OpenCL will not.
For example, if you try nVidia GT240 it will work.
You have to check if you card supports OpenCL.
Other thing is that architecture of AMD video cards is much better can be used for mining, so even very powerful gaming nVidia cards have lower hash speed than mid range AMD cards.
P.S. I recommend you to mine litecoins, as mining bitcoins using video card is not profitable anymore.
For example, if you try nVidia GT240 it will work.
You have to check if you card supports OpenCL.
Other thing is that architecture of AMD video cards is much better can be used for mining, so even very powerful gaming nVidia cards have lower hash speed than mid range AMD cards.
P.S. I recommend you to mine litecoins, as mining bitcoins using video card is not profitable anymore.
My nvidia care has no support for OpenCL, and cannot use CUDA either.
I was reading about these raspberry pi things that cost $25-$35 or so, and use very little electricity.
What about those? ( I noticed that these raspberry pi things don't use windows operating system though, so I would need to get a different operating system it seems in order to use this for mining bitcoins).
I don't know much about the block erupters. I read a bit about that too.
If I exchange my Nvidia card for one of the amd ati cards that is good for mining, would my pc then be able to mine bitcoins, with just putting in an amd ati radeon graphics card?
Just get you a pair of Raspberry Pi units, and install Pi-Miner. Sync the two units with PI-Miner so the first one is on a phase shift of 180 degrees. Use a heatsink on the first, but NOT the 2nd raspberry Pi.
