So my iMac will be here very soon. Im not waiting for the rumored refreshes this fall as i dont think they will be a big enough reason for me to wait. Anyway, my Mac is the top spec iMac with everything standard expect the GPU which is the ATI Radeon HD instead of the Nvidia Geforce. How long do you think this will last me? Everything moves on so quick, so when do you think my iMac just wont be able cut it? My old Dell 9200 lasted me 4 years (2.4Ghz, 320GB HDD, Geforce 7900s). But its too slow to edit HD video now. So when will the Mac succumb to this.