Q: New Apple iMac 21.5-inch: 2.7GHz & Samsung SSD 840

If you're referring to a Mac that as you say...hasn't been released yet...then how on earth would anyone know if you can install it or not?

Johnny_NYC,

Even if it was possible this would invalidate the warranty, why not simply have a Fusion drive installed? Much smarter than trying to open a new machine and possibly ruin it.

The only thing user replaceable/upgradeable on an iMac is the RAM; any other work needs to be done by Apple or an AASP so as not to void the warranty. And no, iMacs are not at all like laptops - the tech has to take off the screen first in order to get to anything. However, the new iMacs may be different and we, as users, would have no idea what Apple is planning - no matter how computer literate we are, there is no way for us to know what the new iMacs will be like on the inside.

Well, I don't have an SSD, so I can't really compare, but I would not consider any desktop computer unless it had a 7200 rpm hard drive (that's the write speed) - some of the new ones show a 5400 rpm drive, which is considerably slower (and quite often used in laptops). I bought a Mini once with a 5400 drive and sold it 4 weeks later - I do a fair share of video editing, and it was just too slow, so I took a small loss and got another iMac instead. So, I'd think you're ok if you go for a 7200 rpm drive - an SSD would be icing on the cake.

If you are even considering changing components on an iMac it is a daunting proposition. Aside from the proprietary screws and fastners there are a multitude of very small connectors withj tiny plugs that require a high degree of dexterity. Now a new issue has surfaced. I just took posession of an i7 Mac Mini and added a SSD. Boy what a crazy OS exists now. It would not recognize the drives (both of them) properly until I did 2 complete Dusk Utility Repair Disks with rebooting inbetween and no startup disk. Then the OS created a Fusion Drive (I'm not sure I wanted one) snd now after 10 hours of OS X installation/repairs I finally have a working system again. Since we don't know what the new iMacs are "system buitl" as the answer is nobody knows what exactly to expect. Neither Apple nor OWC techs could answer the questions my installation created. Unless you want to spend HOURS on the phone and doing work around installs I would cool my jets and wait for better intel as to what you are up against.  Wait a month after the release of the new proiduct, till the Geeks get a hold of some for trials.

I see right away what the problem is. You are trying to fix the drives with Dusk Utility Repair Disks that only works from about 6 to 7:30 pm. Any other time it doesn't work. You should have used Disk Utility Repair Disks.

wait for better intel

That's a good pun, btw.

You are a very funny Guy   I actually got the system working appropriately. Can't say it wasn't a hassle. BTW the new Fusion laced OS will create its own fusion drive if you have the components!!!  Having read numerous articles on how some used Terminal to create their own versions of "Logical Drives" who would have thought that the Internet Recover Disk Utility would do this for you... without you even wanting it!!!    At least it appears to be hapilly installed now 

Very interesting tidbit, RRFS. Presumably, the special DU is automating the manual process for those who do not have the DU that comes on the new models.

For the life of me I don't see what the advantage is. I have an SSD and HDD in my 2011 iMac. I use the SSD to boot the computer. Every thing else is on the HDD. The user folder is set up on the HDD. I determine what to use on the SSD if there is any advantage to do so.

That is the setup I was shooting for, 2 discrete drives but the new 10.8.2 (12C2034) has a different Disk Utility which won't allow the drives to live seperate lives, it Demands Fusion. This could turn out to be a real issue for users like yourself if Apple makes this incorporation universal. My guess is this Fusion iteration will not go away because they are now selling units with the Fusion Drives. I would defintely be cautious at the next update for MtLion, I'll bet it'll be in there. I really wasn't wanting a Fusion drive but such is modern life, I guess.

The build you have is only available for a very few models and includes a special version of Dusk Utility......

http://support.apple.com/kb/HT1633

The rest of us are on 12C60.....(and Disk Utility).