Ok. This is a subtle one. I am looking for some thoughts and opinions from the MacRumors intelligent readership. I have an 'old' iMac. There is some controversy as to which iMac it actually is as the model number/EMC/system profiler do not actually match up. Anyway this is not the issue - unless someone feels like elucidating that for me. So let's say "despite" being A1224, EMC 2133, system profiler and I think this is an: iMac 8,1; 2.66 GHz C2D; 2 GB 800 MHz DDR2 SDRAM (yes before you say it - I am going to up the RAM) I also learn via system profiler that the HDD is a 7200rpm SATA. The ODD shows under ATA and not under Serial-ATA in SysProf, and iFixit.com state that it should be a PATA connection (is this right?). I don't ever use the ODD for anything. Ever. So the two options are: 1) simple: swapping my HDD for a larger one, and keeping the ODD collecting dust, or alternatively carve out a flower-pot from it. 2) installing a larger 2 TB HDD (SATA) in lieu of the current one, AND removing the ODD, placing instead one of these PATA caddies that you can find on eBAY and installing on it a 64 GB SSD to run OS X from. Now the question really is: is it worth it to go for the second option? Is, in other words, running OS X from an SSD which is connected to the motherboard via PATA faster or slower than running OS X from an HDD which is connected to the motherboard via SATA? I sort of like the 'idea' of having my OS on a separate, small, SSD. But cost and hassle here are not negligible. So would I be better off just plonking both OS and files on a mammoth HDD via SATA without messing with the ODD? (I am aware that there is a third option: to put an SSD on my SATA where the HDD currently is, and putting an HDD where the ODD now is via PATA. Speed-wise this would make more sense, but I don't want to do it because I want to get a large (2 TB) drive, and I don't think I'd find one slim enough to fit in the caddy at a reasonable price). I'm looking forward to hearing your thoughtful thoughts on this one. Thanks!