new 8800...choppy video

It could be the psu as the antecs are known to have bad quality caps, which dont like heat,

Antec NeoPower 480- Theres more than likely your problem my friend. I had mine go bad on me. These units are known to use the crap, cheap Fuhjyia (sp?) caps. They are very susceptible to ripples in current and heat. Heres a link to a post by SuperNade regarding this problem Antec SP-400 Innards [Bad caps!]. You can't "dedicate" a 12v line per say as far as I know. You should upgrade your PSU if you ask me. I had a similar setup like yours (Dfi NF4, Opty 170, X1900) and my Antec just couldn't cut it. I had similar stuttering issues like yourself with my X1900. Check your GPU's core temp as well.

well...after consideration...i decided to scrap most of my entire machine and go with a 650i E6600 deal with the Corsair HX620. so once everything gets here ill see if there are any issues still...thanks for the responses.

Yeah I also doubt it was the PSU or the CPU. Those PSU's work just fine and have decent volt/amperage with minor dips under load from my experience with them. Heck I got one powering a dual Opty system with 8 gigs of ram and a Quattro 3500 GPU right next to me. CPU I doubt thats the issue as well since it is a dual core and it shouldn't have any issues.

If anything I'd lean to GPU drivers, System drivers, or just the player itself and the codecs it has. I've had issues in the past where certain players will play videos better than others. It could also be a setting in the control panel.

I know I have no issues with my 2900XT and playing or doing other things while playing EVE at all, heck all the way back to my 9800XT I've never had issues.

it could have been any number of things, but i was in the market for a new machine anyway...so all is well