I plan to fiddle around with settings a little further tonight, but last night I did get it to the point where it wasn't as noticeable and definitely wasn't as distracting.
The nice thing is I can finally crank up the graphical settings in the game and AA and AF and still get pretty steady 50-some fps, which are things I couldn't do with the X800XL. So that definitely makes up for it not being quite as good IQ as ATI, at least for me.
Also, regarding noise, my friend got a 7800GT and it ran full-blast on the fan all the time and you couldn't adjust them and it was obnoxiously loud to me. This 7900GT's fan adjusts and when in Windows it's nearly silent, especially inside my Antec P160 which is a great case. Sure, it gets a bit louder during 3D gaming but that's to be expected - all cards need to be cooled more when the GPU is heating up.
Either way I'm pleased with the level of noise of the 7900GT KO N-584 model from eVGA. Definitely.
Only concern is IQ since out of the box the ATI cards I've owned (9600Pro, 9800Pro, X800XL) did not require any special configuration just to get them to look correct (ie, no swimming textures all over the place). You'd think IQ would at least default at something resembling acceptable settings, but apparently that is not the case with NVidia drivers, at least not for Source games (or maybe specifically CS:S?). Either way it looks a lot better now so thanks to those who made helpful suggestions. I'll continue to adjust things, but my biggest question now is what exactly the plethora of AA options mean:
http://users.adelphia.net/~jrockcls/aa.gif
Q, 9-tap, Gamma, S
If anyone can help by explaining wtf the extra letters after some of them mean, that would be helpful. I'm guessing SS = Super Sampling. What are the other ones?
Also do any of those require SLI'd cards to work properly or are all of those available to my 7900GT?
Thanks!