You'll find information on everything related to the 2011 21.5" iMac computers. I am using this page as a data dump to how I am setting my computer that I started to setup on June 11, 2012.

This is my first exposure to Mac OS Lion (10.7) so there's some OS specific information on this page that some users might find useful.

I have 4 primary uses for this computer: Internet programing, Photos, Audio and Videos.

2011 21.5" iMac - "Mid 2011"

imac Sierra

Apple product sku for this computer was MC309LL/A.

The iMac "Core i5" 2.5 21.5-Inch Aluminum (Mid-2011) is powered by a Quad Core 2.5 GHz Intel "Core i5" I5-2400S (Sandy Bridge) processor with a dedicated 256k level 2 cache for each core and a 6 MB shared level 3 cache. In lieu of a system bus, it has a "Direct Media Interface" (DMI) that "connects between the processor and chipset" at 5 GT/s.

Computer SDRAM Memory

The iMac (Mid 2011) computers have four SDRAM slots in the bottom of the computer and come with at least 4 GB DDR3 SDRAM installed as two 2GB DIMMs into two slots.

The maximum amount of RAM you can install in your computer is 16 GB (a 4 GB SO-DIMM in each slot).

You can use any Small-Outline dual inline memory modules (SO-DIMMS) that meet all of these criteria:

  • PC3-10600
  • Unbuffered
  • Nonparity
  • 204-pin
  • 1333 MHz

You can use RAM module sizes of 2 GB or 4 GB in each slot. It is possible to add 2 4GB in the open 2 slots for a total of 12GB of memory.

Computer Ports

A handy picture of various port locations on the back of the computer.

Configure PHP on OS X Yosemite

Edit your /etc/apache2/httpd.conf and make sure the line:
LoadModule php5_module libexec/apache2/
...exists. I think it's commented out by default in the standard OS X config, but from what I remember, you just need to uncomment it, then re-start Apache:

sudo apachectl restart
And you should be good to go.


If you use your computer on a regular bases, you should consider just keeping the computer on all the time. There is a bit of additional overhead when the computer starts up. By keeping the computer on all the time, your can have instant startup and continue working with the programs your using.

If you have cats, I would suggest moving the wireless keyboard and mouse so that if they walk across your desk they don't accidentally turn on the computer.


The latest shipped version of iMovie is 10.0.2 otherwise known as iMovie 11, some tips on using iMovie.

  • GeeThree will not work with the latest version of iMovie.
  • If you do any work with iMovie 11, you should know about Pre-Key Footage. Using iMovie you can incorporated special effects from other clips into your own movies.
  • Check out YouTube for excellect tutorials on how to use iMovie. (Best thing the tutorials are free!)
  • Not enough special effect with the text tool? You can create special text effects using Keynote and then import the text into your movie.
  • Learn how projects work in iMovie. To improve performance, try to keep the number of library clips to a minimum.
  • Use software like Fission to build better sound tracks.

The computer comes with a SuperDrive, with the ability to burn Dual Layer DVDs. I have had very good luck with various brands:

  • Using Sony and Memorex DVD-DL DVDs
  • Staples DVD-R

I usually purchase my media when it's on sale at Staples or Best Buy. I use to purchase from Meritline but haven't used them in a while. They do sell high quality DVDs at the lowest prices.

Hard Drive

The computer comes with 1 TB hard drive which should be plenty of storage to start with. However, if you do any work with digital pictures and videos and you'll find that the computer disk space starts to shrink. In the long term your better off getting a 3TB external drive for additional storage.

USB Hard Drives
USB Hard Drives

If your looking to add an additional hard drive to the iMac, you should consider your drive options. There's a lot of good deals on 2TB USB drives. The 2011 21.5" iMac only has USB2 ports. While USB3 drives are backward compatible, there is a big difference in speed times between a USB2 and USB3. Maximum speed of USB2 is 480 Mbit/s while under USB3 it's 5 Gbit/.

This weekend it took me 2 hours to transfer 100MB to the external hard drive via USB2. Since I am using this hard drive as a secondard back up hard drive, the speed isn't all that much of an issue. The primary purpose is to free up the space on the primary hard drive for video and photo work.

Photoshop Replacement

It's end of an era for Photoshop. I am not going to pay $800 to upgrade Photoshop CS2 to the latest version. I just don't have that much money to spend on software. There's plenty of other choices in the market.

I ended up purchasing Pixelmator, it contains many of the similar functions that was in Photoshop. The hardest thing for me is to start to learn all the new keyboard shortcuts and how to perform certain actions. I think this is way better than justifing spending $800.

Pixelmator is a beautifully designed, easy-to-use, fast and powerful image editing app for the Mac that has everything you need to create, edit and enhance your photos. I suggest that you add this to your application library. Spend about an hour playing around with it, and watch some of the online tutorials.

Rebuilding iPhoto

Every now and again I have some problems with iPhotos, I find that rebuilding the library is the best solution.

If iPhoto fails to load or crashes on startup, you may need to repair and rebuild you iPhoto library.

To rebuild an iPhoto Library hold down the Option and the command key and click on iPhoto to launch the application.

Depending on what is wrong with your iPhoto library select one of these options:

Repair Permissions
This is probably the best option to start with. If your computer was not shutdown correctly, there may be files that were left open at the time. Repair permission fixes this problem.

Rebuild Thumbnails
iPhoto may have missing or damaged temporary images that iPhoto needs. This option creates those images again.

Repair Database
If the photos in your library don't match what iPhoto thinks it should be, this option will fix that problem. iPhoto looks at what photos are in the library and updates its records accordingly. This will take a long time to process.

Rebuild Database
If nothing else works, use this option. It may take an extra long time and you might lose information about photo tags or albums. Try all of the other options before using this one.

Firewire 800

Check out various options for converting the Firewire 800 port to a regular Firewire port. Example: iWires FireWire 800 to FireWire 400 Mini Cable and Moshi Firewire 800.

Connecting a second monitor

I have a 20" Apple Cinema Display that I want to connect to my iMac, Apple suggest to use the Mini DisplayPort to DVI Adapter. Which the Apple Store sells for $29. Monoprice has it for about $7.