Originally posted by: DJFuji
thatsright,
I'm still using an old SB Live 5.1 card. Much better than onboard sound with my aging KK266 board. However, i'm building a system very similar to the OP's and i'm curious as to whether you can hear the difference between the SB Live 5.1 and the A2/ZS when playing mostly older games (counterstrike, Q3A, UT2004) or when just listening to MP3s or watching DVDs (I live in apartments so i dont play either very loud). Right now i'm using a waaaay old Cambridge Soundworks 4 channel system that i bought in 98-99 i think. I'm planning on using a set of Logitech Z560s with the new system and was wondering if i'd really notice the difference with an upgraded sound card. I'm not what you'd call an audiophile.
		
		
	 
Well I built my 'new' rig back in June 03.  And I cannibalized my old SB Live card I had, and the okay to crappy Yamaha 2-Ch speakers I had.  Then last September I traded up to a Audigy 2 ZS and Klipsch ProMedia 2.1 speakers; a VERY significant and hefty upgrade.  There is a big difference btwn the SB Live and ZS cards.  You notice it most in music (CD's and MP3's) and some games; it just sounds a lot better.  And for me, the best feature is probably the included Graphic Equalizer that is only in the ZS cards.
For games, there is a big difference with the improved EAX 3 sound effects with the ZS over the SB Live.  The EAX environmental positioning and 'warnings' in games like UT2004 are much more pronounced with the ZS cards.  After upgrading to the ZS retail card, I could hear other players footsteps coming up behind me, that I couldn't hear with the SB Live card.  BTW, I didn't know that UT2004 was 'old' yet! LOL.   The 'old' games you mention, I have never played, so I couldn't really say if they will sound any better if you get a new card.  I mean if the 'old' games aren't coded for EAX3 or 4 special sound effects, then you wouldn't notice anything extra if you buy a A2 or A2 ZS.
Couldn't really say anything about the ZS and DVD's.  I don't watch DVD's on my PC, but do so on my HT setup.  Though, if you do hook up your speakers directly to the PC, I know the ZS card has internal Dolby Digital 7.1 EX and DTS ES decoding on-board, which the SB Live can't compete at all.  The SB Live is 16Bit, and the A2+ line is 24 Bit sound quality.  And the A2 and ZS cards also play DVD-Audio disc's for much better sound than ordinary CD's and often in 5.1 sound.
So to make a long winded analysis, short, upgrading from SB Live to the Audigy 2 or A2 ZS is a big jump.  BUT, you really need a nice set of speakers to notice the jump with the Audigy 2 or Audigy 2 ZS.  How good do your Cambridge Soundworks speakers still sound?  It's up to you.  Hope this answers many of your questions, but will probably leave you with more questions 
 
G/L  
Any other  questions, ask away.