Well just a few notes here for particle preformance.

#1. Don''t calculate the particles camera transform for each particle. Do it for the first particle then use this value and apply it to all the other particles. This should improve preformance quite a bit.

#2. Linked lists aren''t exactly the best to use in this situation, because if you set a particle to "dead" you still have to iterate through it to find the next particles address. A dynamic array that''s calculated on startup should improve preformance a bit. Remember don''t delete your particles just set them to "dead". Dynamic allocations/frees eat alot of CPU time.

#3. Make sure your caching the texture your using for your particles don''t load a texture from a file durring the time your particle systems running only on startup. (yes I know this is a stupid point but you''d be amazed at what people do). File IO is very slow.