I'm going to say that SLI is not going to future proof your system. Whats going to future proof your system is going with a single slot PCIe, buying a really kick A card that will last as long as possible, then when a new generation/version comes out that kicks its ass, buy that one, instead of having to search for a second for a pair a year or two after you initially buy. Only go with SLI if you're going to SLI right away. Other wise, I'd say that the Gigabyate P965 S3 or DS3 is your best bet. The S3 costing you only $100 will leave you that extra $150+ for an even more kick ass card or more memory. Plus, the only way you will really see any benefit from SLI is if you have a monitor running at like 1600x1200 or higher.