$800 to spend, need some suggestions

I have about $800 to spend on a computer.
Here is what I am looking at.

AMD HDZ955FBGIBOX Phenom II X4, Black Edition 3.20 GHz AM3 8MB $245
OCZ OCZ2RPR10664GK 4GB PC2-8500 (DDR2-1066) DDR2 Memory x2 at $96 after rebate
WESTERN DIGITAL Caviar?SE16 SATA WD6400AAKS SATA 7200 RPM $64
Sapphire Radeon HD 4890 1GB DDR5 Dual DVI/TVO PCI-Express Graphics Card $223
Rosewill RP550V2-D-SL 550W ATX12V v2.01 SLI Ready CrossFire Ready Power Supply $55

Now I am at $683 but still need a MB and a case.

Can anyone recommand me a MB for 955 cpu and a decent cheap case please.

Yes ditch that rosewill PSU. For one 4890, this PSU would be good:
http://www.newegg.com/Product/Prod [...] 6817341010

MB: http://www.newegg.com/Product/Prod [...] 6813128392

Honestly I think that the 955 is a waste of money. Going with the 940 will save you $80 and it will have almost identical performance. If you want the same performance out of it you can do a light OC of the Bus speed (this is the only difference between the cores of the two processors, the 955 uses the same cores and overclocks to the same speeds as the 940). A DDR3 memory controller isn't worth it IMO, especially since there are no tangible performance gains with DDR3 over DDR2.

Since you are buying the 955 be then you should be looking at a proper am3 mb that uses ddr 3 and then 4 gigs of ddr3 dual channel kit

GIGABYTE GA-MA790XT-UD4P AM3 DDR3 AMD 790X ATX AMD Motherboard
http://www.newegg.com/Product/Prod [...] 6813128378
$125

Patriot Viper 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)
http://www.newegg.com/Product/Prod [...] 6820220371
$98


That will give you the latest AMD platform and will be supported for longer than the ddr2 which is being phased out

Cheap decent case is the antec three hundred

and the corsair $650 tx psu was $80 last time I looked . Much better than the rosewill