What's up guys. I know there's already been some discussion about the new GPU in the 13" model but I'm still a little confused about some things, the shared memory in particular. My knowledge of hardware is pretty limited so any insight would be appreciated. From some tech site: Like most of you I was bummed when I read that the 13" used shared memory... But to be honest, I'm not sure where exactly the bottleneck in performance comes from: is it slower for the GPU to access the system's RAM then to have it's own memory right there (if so, why? I mean isn't the DDR3 RAM pretty fast?), or is it because the main memory already has stuff loaded on it like the OS etc so shoving the GPU's needs onto an already taxed memory just slows things down (but this confuses me too because it challenges my understand of memory... I thought it just kinda held whatever data and the GPU or CPU accessed and processed that data as needed. Or is that the problem right there, that the GPU and CPU are accessing the same memory bank but there's a bottleneck because the GPU and the CPU need to take turns when accessing the memory?)? Or is it something else entirely? Another thing that I don't understand is why the GPU would be limited to 256mb if it's using the system's memory. Would it be possible to just manually allocate more memory to the GPU, or does the GPU's architecture limit it from being able to use more than 256? Sorry for all the questions. I've been browsing around trying to get a better understanding of this, but most tech sites are way over my head.