I have a 2011 iMac I need and update because it is tremendously slow and besides that issue it still works perfectly fine . I don't see the reason on this computer being old I know but not being able to update . need to take in consideration people that still care for there computers and now just because they are older models there is no SOFTWARE UPDATE.
Due to hardware constraints, 2011 iMac can run no higher than macOS 10.13 "High Sierra." Are you running that now?
98% of slow iMac reports here are the result of the mechanical hard drives of the era. In spite of that, an entry level 2011 iMac 21.5" scores 30% faster than 21.5-inch models from 2012 through 2019 with entry-level mech drives. Still yes, that feel slow. We also have a 2011 model still in use.
This is a simple test for the presence of the expected slow hard drive in an otherwise healthy old Mac:
Three "yes" answers = typical slow mech HD issues
As your only complaint as this point is only slowness, the external USB boot solution on a 2011 iMac will exacerbate the current problem and I can only recommend it if that is the only way to recover data. The limitation of your iMac's USB-2 ports, as Servant of Cats points out, is that an external USB 2 or a FW800 boot drive cannot run faster than about 1/4 to 1/3 the CURRENT speed of your internal drive, assuming the internal is healthy.
By the way, the 2011 iMac was the first to have 6GB SATA internal drive bus instead of the 3GB of the 2010 and older models. This is from our 2011 iMac 21.5:
The SATA "Negotiated Link Speed" is a clock-back from 6GB due to being connected to a 3GB SATA drive.
The SATA bus is 6GB but Apple used as 7200rpm 3GB hard drive. Realistically, had they used a 7200rpm 6 GB drive, the speeds would still be under 200MB/sec and that, today, feels slow.
The 6GB drive bus opens the path for an internal SATA 6G SSD upgrade that would do real-world speeds of ~500 MB/sec and feel quite snappy. However given that High Sierra is already losing browser support makes the labor + expense of doing the fast internal upgrade less attractive, and I cannot recommend you go that way except as a hobby/learning experience if you can afford that.
Due to hardware constraints, 2011 iMac can run no higher than macOS 10.13 "High Sierra." Are you running that now?
98% of slow iMac reports here are the result of the mechanical hard drives of the era. In spite of that, an entry level 2011 iMac 21.5" scores 30% faster than 21.5-inch models from 2012 through 2019 with entry-level mech drives. Still yes, that feel slow. We also have a 2011 model still in use.
This is a simple test for the presence of the expected slow hard drive in an otherwise healthy old Mac:
Three "yes" answers = typical slow mech HD issues
As your only complaint as this point is only slowness, the external USB boot solution on a 2011 iMac will exacerbate the current problem and I can only recommend it if that is the only way to recover data. The limitation of your iMac's USB-2 ports, as Servant of Cats points out, is that an external USB 2 or a FW800 boot drive cannot run faster than about 1/4 to 1/3 the CURRENT speed of your internal drive, assuming the internal is healthy.
By the way, the 2011 iMac was the first to have 6GB SATA internal drive bus instead of the 3GB of the 2010 and older models. This is from our 2011 iMac 21.5:
The SATA "Negotiated Link Speed" is a clock-back from 6GB due to being connected to a 3GB SATA drive.
The SATA bus is 6GB but Apple used as 7200rpm 3GB hard drive. Realistically, had they used a 7200rpm 6 GB drive, the speeds would still be under 200MB/sec and that, today, feels slow.
The 6GB drive bus opens the path for an internal SATA 6G SSD upgrade that would do real-world speeds of ~500 MB/sec and feel quite snappy. However given that High Sierra is already losing browser support makes the labor + expense of doing the fast internal upgrade less attractive, and I cannot recommend you go that way except as a hobby/learning experience if you can afford that.
A 2011 iMac has USB 2.0 – not USB 3.0 or better.
In the event that you decide to use an external drive, of any sort, as an everyday startup drive, I would strongly urge you to purchase one of the OWC drives or enclosures that features both USB 3 and FireWire 800 interfaces. (OWC makes these in both desktop and bus-powered portable varieties.)
FireWire 800 is significantly slower than your Mac's internal SATA 3 interface, but it's still much better than USB 2.0.
I don't know what version of the operating system you are running now, but you can upgrade to High Sierra. There is some software will run on High Sierra and may help you extend the useful life of the Mac. In particular, you might want to download Firefox (Extended Service Release) or some other third-party browser (as Safari updates are tied to macOS updates, and some sites may be pushing you to use a more recent browser for compatibility reasons, or security reasons.)
It simply does not have the hardware to run current versions of Mac OS and no you cannot upgrade your 2011 to have current hardware.
if you have a need to run current versions of Mac OS then it is time for a new(er) Mac. Yup it’s that simple.
Your iMac should not be tremendously slow. If is has become so, the most common reason is that its original rotating hard disk drive is and has been operating in a state of failure.
Your question seems to imply that updating macOS would make your Mac run faster. It just isn't so. If you want to fix your Mac, it most likely needs its hard disk drive replaced. That can be accomplished but there is no denying the fact it cannot be economically justified.
But if you want to do that, by all means write back.
We are not Apple and cannot speak for Apple and its policies.
If you'd like to give Apple feedback: Product Feedback - Apple
I have a 2011 iMac I can't update it anymore
