Athlon XP vs. 64bit

Athlon 64 3000+ vs. Athlon XP 3000+ (Barton) w/ 512K L2 cache

The main question is, will i see substantial improvements in performance playing games. I don’t know a lot about comps, but from what i’ve heard is that not many applications can take advantage of the 64 bit. Does this apply to games as well?

I’m also building a new comp…and was wondering if its worth spending 400$ extra if games / windows will run very similar.

Comp 1:

$93 - Antec SLK3700AMB w/ 350W PSU
$90 - ASUS A7N8X-X NVIDIA nForce2-400
$210 - Athlon XP 3000+ (Barton) w/ 512K L2 cache
$189 - PC3200 DDR400 512MB CAS2 REV.2 (OCZ400512R2)
$279 - MSI GeForce FX5900XT-VTD128 VIVO 128MB DDR
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861 + tax

Was wondering if the ram is overkill quality wise?

Comp 2:

$93 - Antec SLK3700AMB w/ 350W PSU
$183 - SUS K8V Deluxe VIA K8T800 more info
$305 - Athlon 64 3000+ RETAIL BOX
$369 - PC3200 DDR400 512MBx2 CAS2.5 (OCZ4001024PDC-K) info
$279 - MSI GeForce FX5900XT-VTD128 VIVO 128MB DDR more info
-----
1229+ tax

Also wondering if I should change ram to something less costly.

What I basically want from my comp…. is for example wise:
-far cry to run smoothly on medium-high settings
-for it to run new games 2 years in the future decently
-not have to upgrade in the comming 6 months

Also should I wait for the new nvidia card to come out…will that drop other vid cards prices a lot?
Maybe I should get a Pentium instead of amd?
How about switching the geforce fx5900xt for a 9800 pro 128mb
[-peep-] I duno, any opinion and all opinions are welcome…maybe build me a comp that u think would be suitable for my expectations.

Oh and btw, these are Canadian dollars if u were wondering.

Should check this new article out.
<A HREF="http://www.anandtech.com/cpu/showdoc.html?i=2038" target="_new">Link</A>