DUAL CORE!!.. I have the same system.. the XPS.. the specs for the system are a bit higher than mine .. mine is Intel Pentium D 830 (3.0GHz) w/Dual Core Technology .
it has 4GB DDR2 SDRAM at 667MHz though which i think i put too much. dunno what I was thinking, should have added RAID to the system but whatever. I love my PC. It runs incredibly smooth. Still have had no problems. I got it 2 weeks ago. All I can say is that you'll like what you have. The double SLI video cards sounds very nice.. mine is a 256MB PCI Express x16 (DVI/VGA/TV-out) ATI Radeon X850 XT Platinum Edition which is good enough for me.