I'm looking at getting an iMac (probably 5k) and so wanting to know which bits make Lightroom and Photoshop run more quickly? I know the minimum and recommended specs but my MacBook is higher than these yet at times still leaves me frustrated. Trouble is how much is the software, and how much is the computer I don't know. With each version of LR I seem to get more and more spinning beach balls, most noticeably when using clone/stamp and then moving the clone reference area it can 'think about it for several seconds, and when first zooming 1:1 on an image. First zoom takes several seconds before the image snaps sharp. My current MacBook (late 2011 hi res) has 2.2ghz i7 quad core, 16gb 1333 MHz DDR3 RAM (upgraded from the 4GB it had when delivered), 1TB SSD from crucial, and AMD Radeon HD 6750M 512MB. I'm guessing the graphics card is letting it down, am I right? What about processor? I'm looking at future proofing so wondered what people would recommend? One of the iMac's I'm looking at has a 3.5ghz processor but it's 'only' i5 not i7 like my current one would this mean it's slower even though it's 3.5ghz vs 2.2ghz? I guess what I'm asking is what does the 'i' number represent? Finally are fusion drives any good? I understand the principle in that it knows which programs etc to move into the flash drive, but if I just imported a load of new photos how would it know to put these into the flash drive as they've obviously not been used frequently as are new. Would they therefore be in the hard drive section and bog the system down? If speeds are 95% as good as SSD then fusion might be good enough, but what I don't want is to have a high spec system slowed down by a slow drive. Any help appreciated. Oh, one other thing, do higher res screens slow things down at all?