It's pretty difficult to go back to 2009 and purchase stuff, or maybe you have something we don't know about already
An i7 ought to help you out with the multi threaded applications.
16GB of RAM should be sufficient if not 8GB.... 4GB is a waste, I can't imagine you've been on 4GB for 2 years....
GTX260??? whoever in the world advised you to go for those cards ever?
Go for a Quadro or FirePro if you're into video editing and stuff like that.
From the specs of your older rig, it looks like it was just a gaming rig (Minimum Requirement Config) and not a video workstation.