Ok so my existing macbook (crackbook to be precise) is really starting to struggle. besides the shell falling off the machine and the dodgy replaced screen its starting to struggle in usage. i just done a format 2 days ago of my machine. it originally ran 10.5 and i worked up to 10.7 however i had to roll back to 10.6 because lion was causing the internal fan to go crazy. so im on 10.6 and im running two flash based files within chrome and both are having fps and lagging issues both in the browser and on the entire machine. they even cause audio to lag and clip at times. Its a 2.1ghz core 2 duo with an x3100 integ, 4gb of ram and a 120gb 7200hd. So im on the market for a new machine. I've had this one since 2008. I want to buy a 15" pro but i have a question relating to the retina display. If osx has to draw a larger resolution on the retina screen will this not effect the gpu, integrated graphics and the cpu when compared to a non retina machine? i know you can say a core i7 with a much more modern integrated graphics and an added gpu and a boat load of ram can handle that without any issues but will i get 4 - 5 years out of the machine like i got with my existing machine? is the machine going to lag up in 4 - 5 years and struggle with content like my current issue or will a top range core i7 mbp live on longer and still be a relatively decent player? if the retina causes the internals to work harder to draw a larger resolution am i better off to get a non retina machine? its cheaper and will last longer?