Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.


macrumors newbie
Original poster
Aug 11, 2016
Hello guys!

So I have this iMac 27" medio 2011. Lately I haven't used it much mostly due to the fact that the computer is SO slow specially when it's just booted. I have checked Disk Utility and the activity tool both seems to give fine results. The CPU has around 90 % of free space when I am using the computer, so I pretend it is not the RAM or anything, but I am not an expert.

When using the computer it gets quite hot, but keeps silent. When the computer has been turned on for a while it starts to work faster. The harddisk has 700 gb of free space, so it is not because of too many files laying around (the harddisk has a capacity 1TB).

I have been wondering if it would help buying more RAM since the computer "only" has 4GB of RAM - but I am not working with heavy software at all.

What are your suggestions? Have you experienced something similar and maybe found a solution? Should I make a completely reset of the iMac?

It runs El Capitan 10.11.6.


macrumors 6502a
Aug 8, 2016
I agree...RAM+SSD!

RAM is 204-Pin 1333 MHz DDR3 SDRAM. Officially supported by Apple are 4x4GB, but if you don't plan to take it to Genius Bar you could go with 4x8GB or 2xYour2GB+2x8GB. An internal SSD drive e.g. 1TB will boot your Mac faster, launch Apps faster and let things go smooth again with El Capitan.

I would upgrade to max if it were the 1 or 2 GB VRAM model (Radeon HD 6970M). If it were the 512 MB VRAM model (Radeon HD 6770M) I would think about downgrading to a legacy OS X 10.6, 10.8 or 10.9, maybe running from an external Thunderbolt SSD and maybe just buying another 2x2GB RAM on the next computer flea market to save the money for the next new Mac!

Did you boot in safe mode to clear some caches? Did you you check when periodic scripts ran last to defrag hdd? Did you repair permissions? Did you disable unused startup scripts, launch services/agents, plugins, accidentally installed fonts etc.? Did you clear browser caches? Did you disconnect from slow internet to see if it´s getting better? You could even prevent reading/writing your 4GB hibernatefile each time your iMac goes to sleep or is waking up, but all that fiddling will probably do just very little on SO slow.

You will benefit generally from everything your drive doesn't have to do. The less RAM you have, the more your drive will do. But maybe a 5 years old drive has a good chance to reach it's EOL and is therefore getting slower and slower. That's another reason why a new SSD can't be wrong.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.