Advice required on mobo purchase

Hi all
This my first post here so pls correct me if I get any forum netiquettes wrong.
Also my 1st time buying a mobo and I need some advice coz I'm really confused!!!
I already have a AMD 64 X2 4200+ processor. Also have Patriot PC2-6400 (800 MHz 2x1 GB) DDR2 RAM enhanced latency (5-5-5-12), 2.0 V. So these are my 1st main concerns wit regards 2 d mobo.

I've read thru quite a few post & reviews but still cant select a mobo while keeping costs low. Where I live, Intel is the main sway n AMD rather unknown so support n info for AMD is poor
I actually have a couple of boards in mind

1. Gigabyte GA-M57SLI-S4 (rev. 2.0)
http://www.gigabyte.co.nz/Products [...] uctID=2539

2. Asus M2N32-SLI deluxe
http://www.asus.com/products.aspx? [...] 2=101&l3=0

3. Asus M2N-SLI Deluxe
http://www.asus.com/products.aspx? [...] odelmenu=2

4. ASUS M2N-E
http://www.asus.com/products.aspx? [...] odelmenu=2

Most of the boards have similar features so m looking for best price. If you know of a better board pls let me know. I'm a mid level gamer so am wondering whether I should get SLi or go in for 1xPCIe x16 2.0 slot. I use a CRT(max resol 1152x864) but will upgrade 2 a higher resl LCD monitor soon. Also I'm not quite clear bout how the RAM power requirements (2.0V) will affect the mobo choice. Lastly for 2 way Sli, what min capacity SMPS will I require?

Will appreciate any advice, thanks for reading!

That is a oxymoron..
1xPCIe x16 2.0 slot is the way to go

In light of getting a mobo that has single slot pcie 16x 2.0 plus all other standard features found this mobo:
Asus M3A
http://www.asus.com/products.aspx? [...] odelmenu=1
Would appreciate your opinion or input on this...
I'm lil lost on whether my RAM will be compatable with the mobo
< Patriot PC2-6400 (800 MHz 2x1 GB) DDR2 RAM enhanced latency (5-5-5-12), 2.0 V.>