Building AMD system - Budget about $550. Need advices

Currently, I have a laptop. Due to I can claim back before the end of financial year (30th June) and I often use the laptop 18hours per day, I want to build a new system to replace the laptop. This is the second time I buy PC. The first PC is using AMD, and I feel it's pretty good. That's why I still choose AMD.

APPROXIMATE PURCHASE DATE: after next week. BUDGET RANGE: $550 - $600

SYSTEM USAGE FROM MOST TO LEAST IMPORTANT: Encoding video, gaming, downloading.

PARTS NOT REQUIRED: I got BenQ G2220HD, 2 sets 4GB-kit Kingston Hyperx DDR2 8500, 2 HDD 1TB each and Soprano VX Case with 430W PSU, I don't need LCD, RAM, HDD, case and PSU and OS. My budget for this system excludes the above parts. Please help me check that the below components are fit with my available components.

PREFERRED WEBSITE(S) FOR PARTS: www.newegg.com

OVERCLOCKING: Yes. Actually I haven't overclocked my system, but I'm going to do that with my new system.

ADDITIONAL COMMENTS: Possibly I will buy one more video card to run CrossFire.

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CPU: AMD Phenom II X4 940 Deneb 3.0GHz Socket AM2+ 125W Quad-Core Black Edition Processor Model HDZ940XCGIBOX - Retail $189.99

Motherboard: DFI LP DK 790FXB-M2RSH AM2+/AM2 AMD 790FX ATX AMD Motherboard - Retail $169.99

Graphic Card: HIS Hightech H485FN512P Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Retail $119.99

DVD Burner: Pioneer 20X CD/DVD Burner Black SATA Model DVR-217DBK - OEM $28.99

CPU Heatsink: XIGMATEK Dark Knight-S1283V 120mm Long Life Bearing CPU Cooler - Retail $39.99

I'd recommend going with this board instead:
http://www.newegg.com/Product/Prod [...] 6813128391
$170 GA-MA790FX-UD5P (make sure to do a BIOS flash, easy via USB)
If you can spare an extra $30 pick up a 4870 instead
http://www.newegg.com/Product/Prod [...] 6814161236
$150 HIS H487F512P


Drop the PSU, and get something else:
http://www.newegg.com/Product/Prod [...] 6817341019
$80 OCZ700SXS 700W

Drop the Kingston RAM
http://www.newegg.com/Product/Prod [...] 6820231166
$55 G.Skill DDR2 1066 (OC's very well)

1. Kingston=Crap, once upon a time Kingston was good. However it all went downhill, OC sucks on it.
2. For the time being a single 4870 WILL BEAT a single 4850. He can get another for x-fire (or even a 4850 for that matter)
3. The Gigabyte is easier to OC for a novice, the BIOS is more easy to navigate. (also not a mixed bag, like ASUS)
4. The OCZ 700 is cheaper, leaving it within his budget. Also has a rebate, unlike the corsair.


Note: If you already have the Kingston, upgrade it to the G.Skill when possible (or when affordable).

@IH8U & computersss: thanks for your advices and I appreciate that.

I got already Kingston RAM 2 sets 4GB-kit 8500 HyperX. So I can't change these components.

About the motherboard, I will change to GA-MA790FX-UD5P. When I was looking for the mobo, I weighed GA-MA790FX-UD5P and DFI LP DK 790FXB-M2RSH. I'm living in Australia and the GA is more expensive the DFI.

HIS H487F512P http://www.newegg.com/Product/Prod [...] 6814161236 is difficult to get in Australia, how do u think if I use HIS H487QT512P http://www.newegg.com/Product/Prod [...] 6814161264 ?

About the case and PSU, due to I change to HD4870, maybe I have to change the PSU and case. It will increase my expenses. I will look for a case and a 600W (or more) PSU, not more than $200 AUD.