"Memory support is the one and only difference between the nForce 790i SLI and Ultra SLI chipset - While the standard nForce 790i SLI officially supports memory speeds of up to 1333MHz, the 790i Ultra SLI can make use of speeds up to 2000MHz. In short then, while both boards support EPP 2.0, the nForce 790i SLI chipset is identical to its bigger brother aside from officially supporting memory clocks above 1333MHz, so if running insane memory clock speeds doesn't interest you, then this chipset will suit your needs without burning quite such a large hole in your wallet."