If you are on Unix, the number of links is not really related to the amount of RAM. I don't know how windows manages memory. How much traffic are you expecting to access those 1,000,000 links?
http://www.postcards.com
FAQ: http://www.postcards.com/FAQ/LinkSQL/
http://www.postcards.com
FAQ: http://www.postcards.com/FAQ/LinkSQL/