Let me say what I do like:
Heatsink - Zalmans are slick.
HD - Good
DVD - Whatever - it don't really matter. But LG is good, I like them.
Motherboard - Wise choice. Can't get better than ASUS.
Antec makes good cases, true -BUT- there's other companies who are not as well known as Antec (brand name-ed) where you can get just as much case for less.
Adding your own Delta or Sunon fans to a good case is no big deal either. Delta or Sunon you ask - only 2 of the most reliable names in cooling fans there are. I assure you, better than what you'd get stock-installed in a case. Don't be afraid to change something else that looks "inferior" at first glance.
Another thing to consider - like what I do - I go for minimalist cases. Yeah, true, way back in the old days I liked my case to look sweet. Not anymore. Now, I couldn't care less if it were a garbage can with wires hanging out of it. It sits under my desk anyways. You could probably get an extra $100-120 worth of system if you thought like that. ( Now that I think of it ... a garbage can for a case would be pretty cool - just imagine how many drives you could jam into that thing

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Further than that - since you're going for a new system - why not get this: Intel Core 2 Quad Q6600 -
http://www.newegg.com/Product/Produ...le-_-Processors+-+Desktops-_-Intel-_-19115017
I don't even own an Intel CPU, but I'm regretting that my X2-6K ISN'T a Core 2.
The opinions:
http://www.tomshardware.com/forum/253265-28-9950-phenom-q6600
And benchmarks:
http://www.expreview.com/news/hard/2007-10-29/1193620830d6602.html
... speak for themselves.
My next system - will be a Core 2 - well - assuming there's nothing better at the time.
Though if you want a Core2 instead - you'll need a different MB. Here's my pick
ASUS P5N-D $134.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131232
P5N-D + Core 2 Duo Q6600 - I'd buy that myself today if I were looking for a new system. If you're looking at that Phenom - I'm sure you'd be even more pleased with this setup.
( Yeah ... this advice coming from someone who's been an AMD user since the 5x86. I'm not an Intel fanboy - I just like good hardware. )
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Another thing you would want to consider is stepping "down" to a dual core.
Core 2 Duo E8500
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115036
Quad core tech is not really supported - and by the time it is supported - the current quad CPUs will most likely be outdated and slow. Stepping back to the absolute top of current supported tech would be a better immediate choice for the next few years. I picked up my Athlon FX55 when Dual cores were getting all kinds of attention. The FX55 is a sweet unicore CPU - packs a huge amount of power - and satisfies very well. I've been VERY happy with that purchase. Now, if I had gotten one of the first Dual core chips instead - like an Athlon X2 3800 - well, how do you think I'd be feeling right now?
Ideally - plan a couple years ahead when building a power build. It's good also to get a feel of the tech. For gaming, right now, Dual cores are the stuff. It's going to stay that way for a couple years at the least.
Besides - when the REAL tech comes out - you don't want to be stuck with a clunker - and right now, you don't want to be stuck with bleeding edge new tech that turns out to be slower than the current good stuff.
( Just like during the HL2 planned release - there was that giveaway of free copies of HL2 with video cards. The release of the game was 2 years after the "free copy of HL2" offer. I bought 2x Radeon 9600SE cards to get 2 free copies of HL2. Radeon 9600SE... ever play HL2 on one of them? What? It doesn't play? Yeah ... well 2 years after I bought the cards I doubt the game would work on them anymore.

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