Re: Graphics Cards
Passmark is a decent benchmark and is a good way to get a ballpark estimate of a card's performance, but to get the full scope of it you need to look at a bunch of different benchmarks. Some programs/games favor Nvidia, some favor AMD, some like higher memory bandwidth, some like higher core count, etc, etc...every card will have strengths and weaknesses. Same with processors...good for a ballpark estimate but look elsewhere to get the most accurate view.
You enable SLI from the driver's monitoring program...either Catalyst Control Center(AMD/ATI) or Forceware(Nvidia). In general, though, it's usually better to get one really good card than to get two cheaper ones. You typically get more performance for the money, and still have the ability to add a second really good card later, provided your motherboard supports it.
Athlon II 635--CM Hyper 212+ ║ GIGABYTE GA-790XTA-UD4 ║ Powercolor HD5770 ║ 2x2GB G-Skill Ripjaws Blue ║ Antec Truepower New 550W ║ NZXT M59 ║ Win7 Pro 64-bit ║ Samsung Spinpoint F3 1TB