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Computer Slow? You Might Not Have Enough RAM for Windows

When diagnosing system slowness, one of the things to review is how much RAM your computer has.

Not only does Windows love RAM, but so do Windows applications. And, of course, the more things you run at once, the more RAM you need.

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RAM requirements only increase over time. It’s common for a machine that once ran well to slow down due to increased RAM usage by the operating system and applications. Doing less is one approach. Where possible, adding more RAM is often the best solution. When buying a new machine, ensure there’s room to add RAM later.


RAM (Random Access Memory) is the memory used to hold the programs running as you use your computer, including Windows itself.

When you turn off your computer, RAM is erased. When you turn it on again, the boot process is mostly about reloading Windows and all those running programs back into RAM.

To a certain point, the more RAM you have, the faster your system will run.

Windows and RAM

Pacman eating RAMI’ve often said that Windows loves RAM. It operates better when you have more than you need.

The trick, of course, is that Windows will run — or try to run — even if you don’t have all the RAM you need. Windows will try to “fake it” by using the swap (or paging) file to make it look like there is more RAM in the system then there really is.

Applications (including most of Windows itself) will use whatever RAM they need, and if the combination of all that demand is more than the actual RAM installed in your computer, Windows moves things in and out of RAM by writing to and reading from disk.

The problem? Disks, even SSDs, are slower than RAM.

The result? Your system slows down if there’s not enough RAM for what you’re trying to do. If you see lots of disk activity while you’re not actually reading or writing files, this might be you.

Degradation over time

It’s pretty easy to not realize you’re using more RAM than you have, particularly if you’ve had your computer for some time.

The problem is this: RAM requirements only get worse over time. Your machine may have run Windows well five years ago, when it only needed X amount of RAM. Today, however, Windows might want half again as much RAM to do the same job, and your machine might not have it.

It’s not just Windows. Applications increase their RAM usage and requirements over time as well. Couple that with Windows, and the combination could mean your machine just doesn’t have enough RAM to do the same job it did a few years ago.1

We also ask more of our computers.  You’re probably doing more with your computer today than you did five or ten years ago. That implies we’re running more software now than we did originally. The result is that a computer that once had enough resources to meet our needs is now only marginally capable.

Two solutions

The first solution is to do less with your computer, if you can. Most often that means trying not to run as many applications all at the same time. Exit one before moving on to the next.

However, that is annoying, and doesn’t solve the underlying problem: Windows and your applications want more RAM.

The second solution, then, is to give it to them: add more RAM, if you can. Particularly for older systems, I recommend installing the maximum amount of RAM your computer can accommodate. That will vary based on your computer make, model, and age.

Of course, someday you’ll run into a situation where you need to run all those apps and your machine is already maxed out on RAM. The only solution then will be to buy a new machine.

RAM and new machines

When buying a new computer, I recommend you ensure the RAM can be expanded beyond what you need today.

My current desktop has 64GB of RAM, and I rarely come close to using it all. Over time, of course, that will change, which is why I made sure the motherboard can be upgraded to 128GB of RAM someday.

Similar RAM upgrades significantly lengthened the usable life of my previous two desktop machines. Each came with an amount of RAM appropriate to their purchase date, but with room for more. And each was eventually upgraded to their maximum capacity.

The bottom line: when it comes to RAM, more is better, and not having enough could be one of the reasons your machine is slowing down.

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Footnotes & References

1: It’s not some conspiracy. The machines you buy today have more RAM than your older machines, and software — both the operating system and applications — take advantage of that. Consumers also expect more of their software, which means it needs more room to work.

13 comments on “Computer Slow? You Might Not Have Enough RAM for Windows”

  1. RAM is definitely faster than SSD used as virtual memory, but when your RAM is maxed out, an SSD can make a world of difference. I have 10-year-old laptop which I maxed out at 8GB RAM, I ran a system backup, swapped my system HDD out for an SSD, and restored the system from the backup. It feels like a modern computer, starts up in under 2 minutes and runs snappy with programs loading quickly and no delays.

  2. I’m the IT guy in our office and this was my solution for a couple of ageing i5 computers.
    Supplied with only 4gb of RAM initially, I added another 4gb (using spare slots and cheap memory) and gave them a whole new lease of life. If I find them struggling again in the near future, swapping the 2gb sticks for 4gb sticks should take them to another new level.

    If I am buying / building a new PC for myself, I make sure the operating system is on an SSD and my installed stuff on a separate HDD just to keep things moving swiftly.

  3. There is another IT truism that comes into effect – a gig of ram in 2 years will cost a lot less than it does today. That makes buying a machine with capability to expand the installed RAM a sensible choice. As for the time it takes to install new RAM – it will take a lot longer to port the OS, applications, data and hardware drivers to a new machine.

  4. The 2nd best thing I ever did for my wife’s Win 7pro pc was up the RAM to 8GB from factory installed 2GB, resulting in a moderate speed increase.
    The best thing I ever did for my wife’s pc recently was to swap out the HDD for a SSD.
    WOW, what a speed difference.
    I was that impressed that, my i5 2500k, Win 7 pro pc will shortly be getting a similar upgrade.

    • @ Brozza ; Microsoft dropped support of Windows 7 in Jan 2020 which basically means it’s a bad idea for the average person to still be using it here in Oct 2020. but assuming Windows 10 likes your hardware, one can still get a free upgrade (free as in 100% free with no catch) to it the last I checked in 2019, which I am assuming would still work here in 2020.

      basically just use the official ‘Media Creation Tool’ from Microsoft (i.e. ) and from there you can upgrade for free. once Windows 10 is registered to your computer you can use the Windows 10 ISO (which can be downloaded using that ‘Media Creation Tool’ and then use something like Rufus to create a bootable USB stick) to clean install Windows 10 to that computer in the future and it will automatically activate.

      if you don’t want Windows 10 for whatever reason… I suggest moving to Linux as at least it will give you a secure operating system to use online etc.

      but yeah, going from 2GB to 8GB would be a rather large all around boost to system performance and I am not surprised the SSD upgrade as it’s a rather large upgrade for general system performance as boot up times are clearly better and program loading times.

  5. I added two 8G sticks to the two 4G sticks already in my computer. I didn’t see much of an improvement. I’ve heard that RAM is like a chain link–it’s only as strong as its weakest link. RAM speed is only as fast as the slowest stick installed. True?

    • I believe that to be true BUT RAM speed is rarely a limiting factor — not something you’d really notice. Ram quantity, however can make a huge difference. My guess is that your usage of your machine was not pushing the limits of the amount of RAM in your system.

    • @ Mike ; RAM speed/timings are not really all that important as those tend to be minimal difference in real world tasks as a general rule from what I have read online. but the amount of RAM you have is clearly more important. but since you went from 8GB (2x 4GB) to 24GB of RAM (i.e. your initial 2x 4GB chips plus the 2x 8GB chips(so four RAM chips in use in total)), depending on your usage, I am not surprised you did not notice much of a difference, if any.

      because I figure unless your running a program beyond the web browser that burns up quite a bit of RAM, many things won’t even burn through 8GB (a lot of people can easily get by with 8GB of RAM), especially if your running the more RAM hog programs one at a time. even the web browser (say Firefox(as I suspect Chrome will eat up RAM even faster)) will take a while to burn up 8GB of RAM as if your just loading up your web browser for a little while, browsing a few sites, with maybe a small amount of tabs open, then closing the browser and not leaving it running for days or longer, there is a good chance 8GB of RAM will be likely more than good enough. but if you have plenty of tabs open and leave your computer/browser running for days/weeks etc, then having 16GB gives one a little boost since your not likely going to use anywhere near most of it up and performance should still optimal.

      I went from 8GB to 16GB in Sep 2020 (I was on 8GB of RAM from May 2012 til Sep 2020), and while there is a bit of a difference for me on some stuff it’s largely the same as I mostly just got a solid buffer now to where I am not close to using all of my RAM where as before when I was on 8GB of RAM I could see my Linux OS was using some swap space (and I was using the ‘vm.swappiness=5’ which helps minimize swap file usage) after the computer has been running a while along with my web browser for several days or longer. but once I went to 16GB of RAM, the swap file does not get used now. I am currently at 39% of RAM in use (when I was on 8GB of RAM not long ago that would have been equivalent to 78% in use) which comes out to around 6.24GB of RAM in use as where I am at now is pretty close to my general usage patterns as it might climb up a bit higher but I can’t see myself going more than 50% tops with 16GB of RAM short of loading up virtual machines (which I raised the amount of RAM these use now that I have more RAM to use) or leaving the browser running while playing a video game etc. but in general I tend to close the browser when playing video games to free up CPU/GPU resources to get maximum game performance.

      if I was using Windows 10, I suspect my RAM usage would increase a bit more. but I have been using Linux (Linux Mint) since Jan 2019 as I have not used Windows 10 since pretty much Jan 2019 or a bit before that.

      p.s. but one could say Leo summed things up in few words than I.

  6. I tend to be of the mindset of one of the following two RAM suggestions for most people… 8GB of RAM will work for many, but 16GB should be safe for the vast majority of people for the forseeable future as I tend to see 16GB of RAM as the ‘sweet spot’ for price/performance. I tend to see 32GB is largely a waste of $ for many people and beyond 32GB is overkill as the vast majority of people won’t even come close to using 32GB of RAM as I would bet most would struggle just to burn through 16GB.

    I was on 8GB (2x 4GB) of RAM from May 2012 through Sep 2020 on the same motherboard but I upgraded to some used 16GB (2x 8GB) in Sep 2020 which is basically the max my motherboard supports but I figure by the time 16GB of RAM is a issue, my computer will be clearly outdated at that point as I plan on using this for the foreseeable future as my current main PC (like in terms of core motherboard etc) is the longest I ever had a main PC without changing to another system as currently my main PC is 8 years and 5 months old and counting (ill probably get a easy 10+ years out of it, especially after my CPU/RAM upgrades this year which the price was quite minimal which made me not hesitate) where as my previous record would have been 6 years and 2 months.

    hell, my motherboard supports 2nd/3rd gen Intel CPU’s (so we are talking pretty much 2011/2012 time frame) as I had a i3-2120 from May 2012 through June 2020 at which point I got a used i5-3550 for a hair under $20 which was a strong upgrade for very little $ as to save money I used my i3-2120 heatsink on the i5-3550 but undervolted the CPU by -0.130v (basically that’s the most I can go and my system remains stable as at -0.140v system instability kicks in and at -0.160v it has trouble booting so -0.150v is basically the most I can even attempt) which shaved off about 13c from max temps and helps compensate for the i3-2120 heatsink I am using on it which lacks the copper contact the official i5 heatsinks have so things run a bit hotter.

    but when I initially bought 8GB of RAM in May 2012, it was plenty as I never even came close to using it (at that time around 4GB of RAM in use was more typical for me where as nowadays that’s climbed to generally the 6.xxGB range or so). but after some years passed you could see that was no longer true as web browsers got more RAM hungry (especially if you leave your browser (I prefer Firefox as it’s less RAM hungry than Chrome is) running for days/weeks with plenty of tabs (say 50-100 or so) open like I do) it starts to burn through a large portion of that 8GB. so it’s like 16GB in recent memory is sort of like 8GB was back when I got it in 2012. currently my system has been up for 6 days straight and browser has been pretty much running for several days now and currently my system RAM use says 39% (which is probably roughly around where I peak for typical usage on Linux(Windows would probably be a bit higher)) in use which means I should be right around 6.24GB in use. so while 8GB would pretty much work, with 16GB I got a solid buffer there as I noticed prior to my upgrade on Linux, it was using a little swap space but since I upgraded to 16GB, it’s not used it since since I am not even close to filling the RAM now. so I guess one could say I got a little bit of a boost going from 8GB to 16GB, but nothing significant. but it does help on the occasion I load up a virtual machine etc as I can allocate more RAM to it without running low on RAM.

    but with that said, I think if someone has fairly light PC use (a little web browsing and not much beyond this) one can get by with as low as 2GB or 4GB on Linux systems since they tend to be less resource hungry than Windows. still, just about everyone should have a computer with AT LEAST 4GB of RAM bare minimum nowadays unless their computer is fairly ancient. but really, anyone who really uses their computer should have at least 8GB of RAM as with 8GB of RAM, you tend to be in that ‘good enough’ range even though 16GB gives you room to breathe and helps ensure RAM won’t become a issue for the foreseeable future. but if someone plays video games on their computer I think 8GB or 16GB is pretty much a must.

    p.s. but I would say for most people if their computer still has a regular hard drive, going to a SSD would be probably the best all around upgrade they can get for a reasonable price, especially if your RAM is at a decent level (say 8GB+ (or at the very least 4GB)).

  7. Leo,

    You say you have a desktop with 64GB and scope to upgrade to 128GB of RAM. What do you recommend as a basic minimum in 2020. I started with 1GB in 2008 but now use two Windows 10 laptops with 8GB, while my wife is on Windows 7 with 4GB. My son just got himself a desktop with 16GB. (He seems to live in a different world to us).

    • It really depends on what you do with your machine. For random person with “average” (whatever that is) needs, I’d probably say 8GB upgradable to 16GB will last for a good length of time.

  8. Hello,

    I have an Asus desktop with 8GB DDR RAM purchased new April 2017, using windows 10. I do tend to have a few programs open at the same time. I occasionally use a video editing program but mostly it’s just Excel, youtube and some reference tools. I kept the RAM from an old desktop I’d bought in 2005. It’s long gone but I took out the ram. Would it be of any benefit to try to fit the older ram into the 2017 computer?

    Thank you


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