what are draw calls basically and what max no of draw calls a p4 3giga hz cpu can handle and what things i have to keep in mind while designing a pc game ? draw call etc measuring software?
As far as I know a draw call is a call sent from Unity to your GPU to render stuff.
You should merge as many textures as possible in a single sheet and use the same material on multiple objects to use batching, batched objects take 1 draw call to render all together. The optimization of a game is not only about the draw calls though. Use the profiler in Deep Profile mode and inspect what operation takes how much percentage of your games performance and try to optimize your physics, scripts etc.