Trying to decide between the dual 2 and 2.3. I'm not too worried about the limited memory expansion of the 2- 4G should be fine. I'm more concerned about the significance of PCI-X slots for potential upgrading. I do VHS to DVD work, presently with a Formac Studio Firewire device, and am curious as to whether a dedicated Capture Card, which could be PCI-X based, should be a consideration at some point if it would deliver higher quality. I know nothing about these cards, but I don't want to limit possibilities. My primary work is video editing/photography. Any advice on this issue? Any other differences between the two machine that I should consider? And is the 2.3 running liquid cooling, or is that just the 2.7? Thanks!