I have noticed my imac (mid 2011) to be very sluggish the past month. I get the spinning colored ball quite abit. Web pages won't load sometimes...browser gives me errors re: page not loading, quite or ..... I also notice even when I try and open and run a program it seems to take quite awhile. Internet speeds seem fine. Over the 5-6 yrs of use I have done LOTS of reading/writing on the hdd. Currently I am running El Captain 10.11.6, 4gb RAM ( i suppose i could add RAM if need be) but its become quite frustrating. I wonder if its time for a new computer? Is there maybe any cheaper alternatives to find out if there are issues occurring? What about doing a clean install and having everything cleared? How would I do that considering the original OS was from 2010-11. Any help is appreciated.