there's a way to help fix that, search for particlecount or something like that.

one weird effect thing i noticed: if you leave sins running minimized and switch back, all firing effects that would've taken place while you were away happen when you switch back.

k, its been sent.
Thank you so much for the support.

when im playing as vasari i get a similar problem, for no apparent reason most of the special fx will switch off spontaneously, you can hear the ships firing but theres no graphics and when ships explode they just dissapear into their debris model with no expplosion (it only seems to happen when playing vasari so far, never had it happen as TEC and i havnt played Advent yet)
sometimes they switch spontatneously back on again but i have no idea what causes this, my machine handles the game fine.
I am using 2x6800gs cards in SLI mode, Alternate frame rendering.

A simple save and reload clears up the problem for me.

Thought I would add my 2 cents. I lose weapon and explosion effects playing as the Vasari as well. As Sunofvich was saying, it just randomly turns off. I have noticed too that with all of the races, that sometimes the dialogue and special effects noises will turn on and off. Perhaps I'm just being blasted by the music and don't notice it, but whenever I click on the sounds option from the menu and then back into the game, the dialogue resumes. I'll be keeping an eye on that more. (and an ear)