The 20 pin 24 pin PSU stuff is all a hoax. Firstly they sell adapters for like 10 dollars, secondly you can just plug in the 20 pin PSU into a 24pin mobo, my cousin did it on his A8n-sli. Just plug it in with the way it fits, leaving 4 pins empty.
Now make sure your PSU supports PFC (power factor control) and short circuit protection, you dont want your sweet system to all burn because of a crappy PSU.
get the fat gfx card IMO. Getting 1 fat 7800 GTX right now, then years down the track when 7800gtx becomes dirt cheap stick another one in. IMO 7800GTX> 7800 GT SLI. SLI is only good for running games at high resolution, it hardly improves FPS on normal resolutions. When you got a 7800 GTX it will do better with normal resolutions.
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QUOTE(DT_Battlekruser @ Feb 15 2006, 10:22 PM)
Yeah, my friend build a computer out of harvested parts once 
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my friend is relying on a crappy 1mb gfx card used for ancient vga comps to run his 3800+ amd 64 server computer, he has yet to buy his 7800GTX LOL.