I am looking at 2 evga cards, both 8800GTS.  
 
One is 320MB:320bit\550MHz core\1600MHz memory\1200MHz shader @64GB\sec bandwidth
 
Other one is 384MB:192MB\650MHz core 1900MHz memory\1620MHz shader @45.6GB\sec bandwidth (PCIe 2)
 
The difference in price is $5 so pricewise is a toss up.  
 
So which one is better?  1st one has faster bandwidth and slower speed.
 
Second one has more memory@slower memory interface, with slower bandwidth, faster speed.
 
So which card is better and which specs are more important (memory, bandwidth, speed, etc)?

Sounds like you are comparing the 320MB 8800GTS with the 384MB 8800GS Superclock.  I have both cards and would say they are close, but the 8800GS superclock is the better card.  The weakness of both seems to be higher res with fsaa.  IMO forget the 320MB GTS exists and grab that supeclocked 8800GS for $110 shipped AR.
 
 

8800gs is actually a better card.
It uses G92, compared to the other one, that uses G80

Thanks for the responses.
 
What about all the tec specs?  What should you look for?  The bandwidth is about 25% better on the 320MB card-does this mean it is really faster?

I never look at the tech specs much anymore.  I look at benchmarks, because 600MHz on one card is not equal to 600MHz on another.  The Architecture is what differentiates all these cards. So the real test is to look at the benches and see what does the best and which suits your needs. And which is in your budget. Obviously a $100 8800GS is not going to be on par with a $180 8800GT.  
 
Oh yeah and don't bother with the 8800GTS 320MB card, its old tech, consumes more power, and isn't as good as the little 8800GS that sucks barely any juice and does a bit better.  
 
What is your budget anyways?

I was looking at 8600 for around $80-$100 (they have really come down in price and have rebates). Then I noticed these 2 8800s.  The 320MB is reg $200-$300 but I can get it for $119 w\rebate.  The 384MB is now at $109.  So...around $100 is looking really good.  BTW I only have a 430W psu with 18amps on 12V-so I am expecting to put some $s into a bigger psu also.  
 
Thanks for the info.

I still say the 8800GS its the best you can get for that price!

I ended up getting the 8800gs-it even dropped to $99.99 w\rebate.  I also found another site that measured performance between the 8800gts and 8800gs-the gs was slightly better, and had newer technology and better power consumption.
 
Thanks for everyones input

Good choice. For $100 you can't beat it.  The GTS320 is old tech now. the new GTS 512 is the hot item.