How Much RAM Do I Need?

Think of the RAM as if it were the computer’s short-term memory. If I were to tell you my phone number could you remember it all or would you need to reach for a pencil and write it down? Could you remember my phone number plus the area code? How about the country code plus the area code plus my phone number?

The point where you need to grab that pencil is the point where your brain has run out of short-term memory, i.e. RAM. There is nothing wrong with writing things down that you can’t keep in your head, but it requires more time and more effort.

This is a fitting analogy for the RAM’s roll inside of the computer. The computer’s processor does the hard work but the RAM temporarily stores all the math problems and the results. The more complex the task, the more RAM it will take to store all the instructions and the results.

If the computer does not have enough RAM to hold everything in its short-term memory, then it has to temporarily write the extra stuff down using an empty part of the computer’s hard drive. This process is called swapping and it significantly lowers the computer’s performance. Just like with the pencil and paper analogy, writing stuff down creates more work for the computer and it takes more time.

So how much RAM does your computer need for professional-grade digital photography? The exact answer varies but I feel comfortable suggesting that 4 GB (Gigabytes) of RAM is about the minimum acceptable amount. Adobe Photoshop and Adobe Photoshop Lightroom gobble up RAM, so the more RAM that you have the happier you will be.

Be careful here not to confuse Gigabytes of hard drive storage space with the amount of temporary storage that the RAM provides. Although both components storage capacities are measured in Gigabytes (GB) of space, hard drives are for long term storage whereas the information stored in the RAM is extremely temporary.

RAM modules are called DIMMs. Most desktop computers today have at least four DIMM slots, but most laptops have only two slots. To get to 4 or more GB of RAM, you will probably need to fill up both available slots on a laptop and at least two of the available slots on your desktop.

When you add more RAM it is generally best to add in pairs of cards. RAM cards differ from one another in three ways. They differ in their chip family, their storage capacity, and in their speed. If you are upgrading, be sure to get an upgrade that precisely matches the variety of RAM—SDRAM, DDR2, DDR, etc.—that you originally had inside of your computer. Since there are so many varieties of RAM chips on the market, I urge you to check with your computer manufacturer or to run a testing program like the one available from Crucial.com before you purchase an upgrade. Be sure that you are getting the right variety of chip before you plunk down the money.

If you are adding additional memory it is also a good idea to make sure that the new RAM modules match the speed of the older memory blocks. The speed of a RAM chip is measured in Megahertz. Like with processors speeds, higher numbers indicate faster performance but these comparisons must be limited to chips within the same family. Although there is usually no harm to mixing faster and slower RAM modules together, all the blocks will function at the slowest speed.

If you are buying a new computer and you have the choice between two different speeds of memory within the same chip family, then I would probably splurge on the faster stuff. For some shoppers there might also be a choice between “ECC” and “Non ECC” chips. ECC is the abbreviation for Error Checking Chips. Error Checking sounds like a good thing but for photographers there is little performance benefit. The Error Checking feature that this RAM offers is far more important for servers and large business databases than it is for home or individual office computers.

Installing more RAM does involve poking around inside your computer. With most desktop computers it is a fairly easy straightforward process that requires nothing more than a small screwdriver. Laptops can be a bit tricker. You can do this work yourself or you can take your computer to a qualified technician and have them add more RAM for you.