building system - need some parts advice

Here's what i have so far:

[*:7f9145f98b] (4*) HDD 320GB 7200RPM S-ATA300 Seagate 7200.10 16MB Ca
[*:7f9145f98b] ASUS A8V-XE. AMD64/FX.S939 (?: RAID 5, 4+ sata, pci-e 16x, 5.1 onboard sound, LAN, dual channel DDR400, SATA2, …)
[*:7f9145f98b] Cooler Master Centurion 534 (Silver)
[*:7f9145f98b] Spire RockeTeer IV 600W PSU
[*:7f9145f98b] S40 Sapphire ATi X1600 XT 256DDR3 PCI-E TVout DVI
[*:7f9145f98b] LG DVDRW+/- 16x DL LightScribe (black/white?)
[*:7f9145f98b] AMD Athlon 64 X2 4200+ (sAM2 socket?)
[*:7f9145f98b] (2*) ? CAS 2,5, DDR2 400 (?), 1GB


[*:7f9145f98b]the hard drives seem to be a solid choice.
[*:7f9145f98b]The mobo i checked and does have 4 sata, pci-e 16x, 6channel sound, 100mbit LAN, dual channel DDR400. Not sure about RAID5, if it's DDR2 (i assume so), or sata2.
[*:7f9145f98b]Case seems solid choice.
[*:7f9145f98b]600W should be plenty. Overkill even.
[*:7f9145f98b]For the graphics card i went with an X1600. Solid card with nice price, i think. Could have gone X800 which - despite lower numbering - is probably faster (even with half the memory) but for 70 euro more it's not worth it to me. Should blow my radeon 9600 out of the water for sure.
[*:7f9145f98b]DVDRW seems solid. I like LG, and lightscribe was only a wee bit more so what the hell
[*:7f9145f98b]Processor: i would prefer dualcore AMD, so i went with the Athlon 64 X2 4200+. The 4600+ and 5000+ have big pricehikes. The numbers would suggest i could get a 10 or 20% performance increase so i am tempted, but it just never works out that way and i'd rather save some money (and hey, maybe upgrade just this and the Gfx in a year or two).
[*:7f9145f98b]The memory i couldn't choose. I *think* it's PC400 but i couldn't find DDR2 anywhere and if i recall correctly PC400 (like PC533, PC800, ...) is pentium memory. But then PC800 existed 2-3 years ago (RDRAM was it?) so it's unlikely it's still that. Anyway, i'm confused so i didn't know which to pick. I've listed some specs i would *like*, if the price's okay.

I'm using one site to get my stuff from (pretty wide selection), it's rather cheap and fairly convenient (far as getting, warranty, etc). If you make suggestions i would prefer they come from those lists, it's not english but the name/price should still be obvious.
[*:7f9145f98b]Internal SATA HD: http://www.computeratelier.com/ind [...] goryID=306
[*:7f9145f98b]Mobo: http://www.computeratelier.com/ind [...] goryID=303
[*:7f9145f98b]Case: http://www.computeratelier.com/ind [...] goryID=274
[*:7f9145f98b]Power Supply: http://www.computeratelier.com/ind [...] goryID=276
[*:7f9145f98b]Gfx: http://www.computeratelier.com/ind [...] goryID=349
[*:7f9145f98b]DVDRW: http://www.computeratelier.com/ind [...] goryID=262
[*:7f9145f98b]CPU: http://www.computeratelier.com/ind [...] goryID=304
[*:7f9145f98b]Memory: http://www.computeratelier.com/ind [...] goryID=301

Screen is current LCD with max 1366x768 resolution (though i'm confused, some apps run it at 1360x768 instead... but no biggie).
Keyboard is ZBoard, mouse is Logitech MX510. Speakers are some nice 5.1 set. These things will not be replaced.

Thanks for your time.