Wanted to have more performance with my Mac Mini 2011, Still think Solid State drives are expensive and also I had another spare 500Gb hard drive that was almost a perfect match to the installed hard drive.
You can see my performance now:
So these are the steps it took to get My Mac Mini 2011, 2.3 GHz Intel Core i5 installed with another hard drive.
First I needed to purchase the other hard drive cable, so looking on the internet I found a computer thats has a cable and all the tools you will need for the job.
Go to http://www.ifixit.com and check out the parts and tools. I received them with in a couple of days. Watch the install video a couple of times. Overall the job took around a hour. Be careful as everything is really small.
One of the small problems I had was the installation of cables. They only need to be press back on to the connectors.
If you find that you need to do a disk repair for permissions the Disk Utility doesn't seem to be able to do it. So instead run this command sudo diskutil repairPermissions / at a Terminal window.