Upgrade your RAM

onfusing RAM with file storage such as a hard disk is forgivable – after all, RAM stands for Random Access Memory, and someone could think that a Mac ‘remembers’ the files you store on it in something called memory.

But a computer uses RAM as somewhere it can stick an ever-shifting collection of stuff so that it can get at it quickly to process it; it’s not really like human memory at all.

Here’s an analogy (but as with all analogies, don’t try to push it too far!): if you’re tired and stressed, you can only deal with one thing at once; if someone gives you another task to do, you have to put down the first one so you can concentrate on the second. That’s a bit like how a computer is with a small amount of RAM. It has to constantly read in new information from your hard disk, and if there’s not enough room in the RAM for everything you’ve asked it to concentrate on, it has to dump out some bits back to the hard disk. Since hard disks (and SSDs, to a lesser extent) are dramatically slower than RAM, this process can make your Mac seem hugely sluggish. Give it lots of RAM,

Cand it can ‘concentrate’ on loads of things at once, and won’t need to be paging stuff to and from your storage as much; it’s especially important to give your Mac enough RAM if you’re asking it to run and switch between many apps at once.

But what is ‘enough’ RAM? These days, a rule of thumb is that 4GB is feasible though a little tight, 8GB is a good balance for most people, and 16GB or more is recommended for anyone doing anything highly involved or complex – creative projects with video and high-res pictures. The great news is that so long as your Mac can have its RAM upgraded, it’s the easiest, cheapest and often most effective upgrade you can do to it. We recommend buying your RAM from a company such as Crucial whose system will ensure you’re getting exactly the right RAM for your machine, and when it arrives all you have to do is open up your Mac – the guides on ifixit.com can advise on how – and then pop out your old RAM and slot in your new. The RAM will have little clips holding it in place, but you just ease these apart before pulling the RAM out. Handle the chips carefully by their sides – avoiding the metal connectors – but in most cases you don’t have to worry about I have a Late 2012 27-inch iMac and I maxed out its RAM to 32GB. I never get ‘out of memory’ errors or slow performance in demanding apps I use such as Parallels Desktop. If you have RAM-hungry programs, always upgrade the memory to the max end of

your budget. using one of those anti-static wrist straps you might have seen recommended.

(While your Mac’s open, it’s a good idea to blow out the dust from the vents and fans, since overheating can cause slow-downs of its own; only use proper compressed air cans for this.)

Spare slots

In some cases your Mac will have spare slots into which you can fit extra RAM (System Information will tell you this) but it’s more common for you to have to ditch your old RAM when you replace it with more.

In any case, on Macs with integrated graphics chips, you should install RAM in matched pairs (both in terms of speed and capacity) for better performance. Companies such as Crucial sell their upgrades as already-paired ‘kits’.

Sadly, Apple has started soldering the RAM in place in computers such as the MacBook Airs, later Pros, smaller iMacs and latest Mac mini – these can’t be upgraded, and if this is you, there’s nothing you can do save sell the whole machine and spec a new one with more RAM.