回答“CPU upgrade 2.0GHz to 2.8Ghz ( C2D Extreme X7900 )”This thread is great! I installed an SSD in our iMac7,1 in 2012, and it has been the kids' workhorse, and a piano (USB 88-key keyboard), ever since. During that project, I also installed a C2D on the first-gen 2001 iMac. Need Penryn for macOS Sierra, the Santa Rosa refresh. Ordering my T9300....