New PC build... need check of parts

This will sound old... but I've been reading these forums for the past couple weeks contemplating building myself a system and the more I read the more I want to build my own rig. I'd like this to be around $800... cheaper is better.

I plan on using this computer for work (I do simulation work, run Matlab, Mathematica), personal media (some video encoding, simple watching movies and listening to music), and also I like to play games (WoW, Witcher, Supreme Commander, Hellgate: London, SC2/Diablo3 when they come out). Sometimes I even do all these things at once... not well mind you but I try.

I am using a 22" Acer AL2216W (1680×1050, 5ms response). I don't think I'll do CF but I'd like to keep the option open even if the 2nd card only uses PCI-e 1 and not x16. I will OC eventually, I'll do this earlier than CF.

So here are the parts I was considering for my purposes:

Video Card - ATI HD4850
1. Asus http://www.newegg.com/Product/Prod [...] 6814121253 $188 ($158 after MIR) comes w/ free Alone in the Dark game
2. HIS http://www.newegg.com/Product/Prod [...] 6814161235 $175 ($155 after MIR) comes w/ free GRID game
I don't know which one is better... I haven't heard much about HIS and I know Asus makes good cards, at only a ~$3 difference I'll probly go w/ Asus.

CPU - Q6600 Kentsfield 2.4GHz Quad $190
http://www.newegg.com/Product/Prod [...] 6819115017
Read it's a good OCer and will last me for a good while... I know C2D is better for games but I think the quad is better long-term and multitasking.

Mobo- Here is where I need some help... I'd like to OC in the future and consider CF. The cards I've been looking at are:
1. Biostar TP43D2A7 http://www.newegg.com/Product/Prod [...] 6813138122 $90
I imagine this one doesn't have CF support being a P43 board but I read it's a good for OCing.
2. Asus PQ5 Pro http://www.newegg.com/Product/Prod [...] 6813131299 $140
I know this will do CF but I don't know if it's any good at OCing.

RAM - Getting 2x2GB. From what I read here the 4-4-4-x are the way to go:
1. OCZ SLI-Ready Edition 4GB http://www.newegg.com/Product/Prod [...] 6820227269 $98 ($63MIR) 5-4-4-15 at 2.1V
2. OCZ Titanium XTC 4GB http://www.newegg.com/Product/Prod [...] 6820227270 $96 ($66 MIR) 4-4-4-15 at 2.1V
3. mushkin 4GB http://www.newegg.com/Product/Prod [...] 6820146726 $105 ($85 MIR) 4-4-4-12 at 2.1V
Some help here appreciated.

Case- I want something with good cooling but not really flashy (I'm not into that whole LED thing):
COOLER MASTER RC-690 http://www.newegg.com/Product/Prod [...] 6811119137 $85 ($70 MIR) Has plenty of fans and looks nice. It does have the PSU on the bottom which may or may not be a problem. Also does this have enough space for aftermarket cooler (say the Rifle or Arctic cooler 7?).


PSU - I think I calculated about 350W or so without OC and a single GPU... I think 600W should do fine for OC.
1. OCZ StealthXStream 600W http://www.newegg.com/Product/Prod [...] 6817341010 $80 ($45 MIR) Has 4 12V rails @18A each... and at $45 after MIR I can't see a better option. Is this a good PSU company?

Case/PSU combo- Not sure this is the best way to go but I'm throwing it out there....
1. Antec Sonata III 500W http://www.newegg.com/Product/Prod [...] 6811129024 $100 Saves ~$15 from the separate PSU/case but has fewer fans and less wattage.

CPU cooler - I will get his in anticipation of OCing...
1. ARCTIC COOLING Freezer 7 Pro http://www.newegg.com/Product/Prod [...] 6835186134 $32 Heard good things about this one.
2. XIGMATEK HDT-S1283 120mm Rifle http://www.newegg.com/Product/Prod [...] 6835233003 $37 ($27 MIR) It's the Rifle...

DVD/CD
1. LITE-ON Black http://www.newegg.com/Product/Prod [...] 6827106073 $26 Lightscribe on sale...

HDD - I have a SAMSUNG Spinpoint F1 HD103UJ 1TB 7200 RPM that I use as an external with my laptop that I could use. What I was thinking of doing was to get a small HDD for OS/programs and use this 1TB drive for data files and to easily move data b/w my laptop and desktop. I don't know what's a good HDD to get though.

Complete list on newegg http://secure.newegg.com/WishList/ [...] er=8663692

So total for this build is: ~$846 before shipping/tax (~$750 after rebates before shipping/tax).

Please give me any suggestions for changes or if any of these components are too much/little and if they are all compatible.

Thank you for your time and efforts.

Go with the rifle if it'll fit, and the retention bracket. Much better cooler, although larger. I see no major problems with it since you won't be doing any intensive gaming or anything. Good case for cooling w/o led or side panel.