It would be faster yes, so long as the texture is big enough to hold all your images. It would be ideal to put your entire game graphics on a single texture. If not you have to be careful that you group or batch your objects so that you switch textures as infreqently as possible.
On my iMac running Vista, which is a an Intel Dual Core 2 @ 2GHz with ATI X1600 graphics, I had to adjust to about 8000 particles to get 60fps. It bombed out when I tried 100,000, but 50,000 worked at a few frames per second. Somehow I am thinking this is still slow compared with what I've seen in OpenGL.
I also agree triangles are probably not much benefit compared to quads - your triangle has to cover as much space as 2 quads in order to fit the same-sized quad inside it, which means more alpha tests/overdraw.
On my iMac running Vista, which is a an Intel Dual Core 2 @ 2GHz with ATI X1600 graphics, I had to adjust to about 8000 particles to get 60fps. It bombed out when I tried 100,000, but 50,000 worked at a few frames per second. Somehow I am thinking this is still slow compared with what I've seen in OpenGL.
I also agree triangles are probably not much benefit compared to quads - your triangle has to cover as much space as 2 quads in order to fit the same-sized quad inside it, which means more alpha tests/overdraw.