If you wish to have an SSD drive in a 27 iMac (mid-2010 onward) you can self install it, saving money and giving you the option of the latest SSD technology. Heres an overview of what you need, how to do it and an explanation of what was done.
240GB Corsair Force SSD; Mac OS X only supports the Sandforce controller and this has it, plus its a big name with a huge reputation. It out performs the Toshiba and begins a new era in reliability, if youre upgrading your iMac and they havent released TRIM support on Mac OS X yet and/or are still on the same SSD option as at release date for the Mid 2010 iMac, get one of these instead.
Required Parts
You will need:
* Left Angled SATA cable
* SATA Power Y-Splitter (male to 2 females)
* Pozidrive T0 screwdriver
* T8 and T10 screwdriver
You should have:
* 2x Suction Dent
* Anti Static Wrist Band
* Compressed Air
* Heavy Duty Sticky Back Velcro
* Screen Lens Cleaning Cloth
Warning
Do not try this if you have no experience with computer hardware. This was my first time inside a Mac and I can tell you its very compressed inside. If you break your Mac its your fault and you will have to pay to get it repaired; I give no warranty with these instructions.
Before you begin
Make sure you have plenty of time; it took me about 3 hours in total, however I didnt have a how-to guide to follow only pieces of information from various forums. If I were to do it again it would probably take no more than an hour.
About the hardware
This is a Mid-2010 27 iMac 11,3 with a Core i3 3.2Ghz processor and a 1TB hard drive. There is space for a second drive. For the SSD I got the Corsair Force 240GB model for the install.
Removing the glass
Put each suction cup in the top corners of the screen. Gently pull one away then the other. Its very easy, you can do it with your fingers if you dont have suction cups. The glass is held in place by magnets so theres no unscrewing etc at this stage.
LCD Display
Lay the Mac down flat to aid with the removing of the screws. There are 8 screws in total, 4 on either side. Use the T8 screwdriver to unscrew them. Theres casing behind the screws so no chance of them dropping into the Mac.
The 27 display weighs 20lbs. and lifting it up the first time can be tricky. You need to get your finger underneath the top left and right magnets to lift it. Do one side first, then the other. The display lifts by only about 30 degrees before the wires on the back of the display restrict you. Gently lift the display and then rest it on your hand so you can begin removing the wires.
The first wire is on the right hand side. It appears to have holding clips but doesnt, simply pull horizontally moving the casing left to right to remove.
The second is in the middle of the display and is connected in three places. The larger connector has grips which must be squeezed on either side of the connector to free it. The second and third simply pull out horizontally.
To the right of the connectors you just removed there is another very small cable for the LCD heat sensor. Simply pull it out horizontally.
Then over to the far right hand side, behind where the first cable was, is the forth cable. It is plugged in the other way round so get your hand behind it and gently pull horizontally away from you.
You can now lift the display upward and then pull towards you to remove it from the Mac.
Logic Board
Now you are in your Mac you can see there is a large logic board toward the top/middle of your Mac spreading right across it. You need access to the underside of it, so must either remove it or lift it up enough to get the SATA cable in.
There are 8 screws in total what you must remove in order to get access to the underside of the logic board. See the image for the location of the screws.
At this point you must decide if it is necessary to remove the logic board. Its not as bad as it may seem, make sure you take note of what you are unplugging for when it comes to plugging everything back in. Dont worry if you get one wrong it wont short the board from my experience. (you are wearing the anti-static wrist band, arent you?)
This is the male and female part of the SSD drive connection. It is just above the stock HDD and can be accessed if you unscrew the logic board and lift slightly. Dont worry about breaking the board, if all the screws are undone it should lift up and out anyway.
You will need to remove this from the top of the logic board if you are going to lift it up and/or take it out. It simply pulls back from the board, pull firmly horizontally to remove it. There is no chance of breaking it, its designed to be pulled out. I didnt know about it and pulled the logic board out with it caused a bit of a loud sound as the board was at an angle so beware of this.
If you need to remove the logic board dont forget to remove the RAM from the other side of the machine, otherwise youll have to prise it out!
This is the logic board being removed. There are 3 cables underneath the board so make sure you take note of that when removing it. And dont forget, there will be 4 when you put it back in.
Heres the board fully removed looking good so far. Now you need to get the sticky back velcro and put the SSD in place.
Heres the Mac re-assambled, you can see the SSD fits in place nicely. Notice the Power Y-Splitter is rather compact in its home thats the 6 inch version.
Close up of that SSD drive nicely in its new home, again, look at the space the Power Y-Splitter has, dont be tempted by the 50cm version, 20cm/6inches is plenty.
Finally, put the Apple Mac OS X install DVD in the SuperDrive and press/hold down D while booting up. Run the AHT utility to check everything is OK!
Warranty
I didn't have to remove any screws with warranty stickers on them and everything went back together nicely. I'm not saying you won't invalidate your warranty, but everything I did I could undo.
-youds
240GB Corsair Force SSD; Mac OS X only supports the Sandforce controller and this has it, plus its a big name with a huge reputation. It out performs the Toshiba and begins a new era in reliability, if youre upgrading your iMac and they havent released TRIM support on Mac OS X yet and/or are still on the same SSD option as at release date for the Mid 2010 iMac, get one of these instead.
Required Parts
You will need:
* Left Angled SATA cable
* SATA Power Y-Splitter (male to 2 females)
* Pozidrive T0 screwdriver
* T8 and T10 screwdriver
You should have:
* 2x Suction Dent
* Anti Static Wrist Band
* Compressed Air
* Heavy Duty Sticky Back Velcro
* Screen Lens Cleaning Cloth
Do not try this if you have no experience with computer hardware. This was my first time inside a Mac and I can tell you its very compressed inside. If you break your Mac its your fault and you will have to pay to get it repaired; I give no warranty with these instructions.
Before you begin
Make sure you have plenty of time; it took me about 3 hours in total, however I didnt have a how-to guide to follow only pieces of information from various forums. If I were to do it again it would probably take no more than an hour.
About the hardware
This is a Mid-2010 27 iMac 11,3 with a Core i3 3.2Ghz processor and a 1TB hard drive. There is space for a second drive. For the SSD I got the Corsair Force 240GB model for the install.
Put each suction cup in the top corners of the screen. Gently pull one away then the other. Its very easy, you can do it with your fingers if you dont have suction cups. The glass is held in place by magnets so theres no unscrewing etc at this stage.
Lay the Mac down flat to aid with the removing of the screws. There are 8 screws in total, 4 on either side. Use the T8 screwdriver to unscrew them. Theres casing behind the screws so no chance of them dropping into the Mac.
The 27 display weighs 20lbs. and lifting it up the first time can be tricky. You need to get your finger underneath the top left and right magnets to lift it. Do one side first, then the other. The display lifts by only about 30 degrees before the wires on the back of the display restrict you. Gently lift the display and then rest it on your hand so you can begin removing the wires.
The first wire is on the right hand side. It appears to have holding clips but doesnt, simply pull horizontally moving the casing left to right to remove.
The second is in the middle of the display and is connected in three places. The larger connector has grips which must be squeezed on either side of the connector to free it. The second and third simply pull out horizontally.
To the right of the connectors you just removed there is another very small cable for the LCD heat sensor. Simply pull it out horizontally.
Then over to the far right hand side, behind where the first cable was, is the forth cable. It is plugged in the other way round so get your hand behind it and gently pull horizontally away from you.
You can now lift the display upward and then pull towards you to remove it from the Mac.
Logic Board
Now you are in your Mac you can see there is a large logic board toward the top/middle of your Mac spreading right across it. You need access to the underside of it, so must either remove it or lift it up enough to get the SATA cable in.
At this point you must decide if it is necessary to remove the logic board. Its not as bad as it may seem, make sure you take note of what you are unplugging for when it comes to plugging everything back in. Dont worry if you get one wrong it wont short the board from my experience. (you are wearing the anti-static wrist band, arent you?)
If you need to remove the logic board dont forget to remove the RAM from the other side of the machine, otherwise youll have to prise it out!
Warranty
I didn't have to remove any screws with warranty stickers on them and everything went back together nicely. I'm not saying you won't invalidate your warranty, but everything I did I could undo.
-youds
I won't really benefit off this but I'm sure there are plenty of people who are more than thankful for this 
