Hey @
a5cent, thanks for the reply.
I meant RAM and I also meant GB. Wouldn't you agree that storage is much less related (particularly with regard to volume) to performance? I will say, though, that Daniel Rubino's comments about a regular hard drive vs a solid state drive have been something that has rung true with me in terms of performance now that I'm back on an HDD.
For most of the people I know, they fall into the heavy web browsing / heavy email category. I've seen different devices sold at different price points and was really wondering what's a sucker's buy and what's overkill. I've seen orders for Macs that include memory sizes that were pretty insane by PC Standards and was just wondering where the huge differential is.
Okay. You might already understand this but first some terminology:
RAM is an abbreviation for 'Random Access
Memory'. That's why the terms '
Memory' and '
RAM' refer to the
same thing. RAM is transient, that means all its contents
are lost when the computer is turned off.
Storage is persistent, that means its contents are
not lost when the computer is powered off. If we'd have enough RAM to load up every program we'd ever need, and could guarantee the computer would never lose power, a computer would work just fine without storage.
Both
RAM and
storage have the same basic job... to store zeros and ones. Given two HDDs, the one that can store more zeros and ones is said to have the higher capacity. For
both RAM and storage, capacity is measured in bytes, megabytes or these days, in gigabytes [
GB]. That's similar to the way in which a gas station's capacity to store gasoline underground is expressed in gallons.
With this I want to make clear that the sentence "I meant RAM and I also meant GB" doesn't really make any sense. It's the same as saying "I meant Gatorade and I also meant gallons" rather than "I meant Gatorade and also meant Coke".
So, what we're actually talking about here is
RAM and
storage. In addition to a capacity, both RAM and storage also have bandwidth, which expresses how quickly RAM and storage can exchange data with other computer components. Taking our gas station analogy, bandwidth would be the rate at which the pump can transfer gasoline into your truck's gas tank.
Storage capacity [GB] generally has no influence on performance. You need enough space to store all your programs, your data, and an additional 10% - 20% space for the overhead associated with the filesystem and for tasks related to file system maintenance. If you don't have enough storage capacity, you just won't be able to save/store all your stuff. If you have more than enough storage capacity, you'll just have some reserve and empty space. Neither affects performance in any way.
Storage bandwidth [MB/s] impacts how quickly data can be transferred between storage and RAM. This can have a huge influence on performance, but only in very specific scenarios like when you launch a program (read from storage), boot the OS (read from storage), or save a large video file (write to storage). In all those scenarios, a lot of data is transferred between storage and RAM, so improvements to bandwidth are very noticeable. These are exactly the scenarios where using an SSD results in a large performance advantage over using a HDD, because SSDs have much higher bandwidth. However, storage bandwidth has absolutely no impact on how quickly your computer can run a game, or recalculate a very complicated excel sheet. Those things don't transfer data between storage and RAM, so they aren't impacted in any way whatsoever. If they were slow before installing an SSD, they won't be any faster afterwards either.
RAM bandwidth [MB/s] impacts how quickly data can be transferred between RAM and the computer's CPU. For the average Office, Mail, Web browsing user, this is probably almost irrelevant. In other scenarios it can make a notable difference (particularly for 3D gamers who don't have a dedicated graphics card), but when it does and does not make a notable difference can get complicated.
RAM capacity [GB] is very poorly understood by most people. Every program that is loaded (e.g. Photoshop, Office, etc) and every file that is opened (e.g. an image and a spreadsheet) occupies space in RAM. As long as there is enough space in RAM to hold everything the user requires, there is no performance benefit to be had from upping RAM capacity further. However, as soon as a user launches more programs and/or loads more data files than can fit into memory, a computer will start swapping whatever it thinks is least important out to storage. That can make things quite a lot slower, because if the CPU ever does require something that was swapped out to storage, accessing that will be hundreds (SSD) or thousands (HDD) of times slower than if it still resided in RAM. So, not having enough RAM can slow things down. Upping RAM can then drastically improve performance, but only up to the point where RAM capacity exceeds that which is required. After that point, increasing RAM capacity further will do absolutely nothing for you. That last part is what most people get wrong. It's a widespread misconception that having more RAM will always improve performance.
Hopefully this helps you realize that the statement someone made above (if a computer can boot in under 10 seconds then it is fast) is too simple to be accurate. Measuring how long it takes a computer to boot will tell you exactly that, but not necessarily anything more. A computer may have a very fast SSD and 2GB or RAM, which would allow it to boot Windows 10 in 5 seconds, but still have a middling CPU and not enough RAM to perform other tasks quickly.
So, how much is enough RAM? It depends on the OS and what the user does.
For Windows 10:
[TABLE="width: 500"]
[TR]
[TD]
2GB[/TD]
[TD]Only for people who never open anything more than a single browser instance with a single tab.[/TD]
[/TR]
[TR]
[TD]
4GB[/TD]
[TD]For people who do nothing but Office, e-Mail and browsing, there is still little reason to have more. I currently have opened 12 browser tabs in two instances of Firefox, MS Word and Outlook requiring a total of 3.1GB.[/TD]
[/TR]
[TR]
[TD]
8GB[/TD]
[TD]For heavy multitaskers who open a lot of programs simultaneously, or people who digitally touch up their personal photographs with something like Photoshop. A lot of computers ship with 8GB of RAM today so it's also becoming just standard (RAM is also pretty cheap). Some will want 8GB just in the interest of future-proofing, even if there is no immediate benefit over the 4GB option.[/TD]
[/TR]
[TR]
[TD]
More[/TD]
[TD]This starts getting more complicated. Usually only useful for professionals or pro-sumers and gamers. If you need this, you'll likely already know why.[/TD]
[/TR]
[/TABLE]
For Macs, I'd say there are two reasons why it makes sense to have somewhat more RAM:
- Macs are often used for image editing, which already puts us in the 8GB bracket
- A lot of people with Macs will run Windows in a virtual machine. So, in addition to OSX, they are also running a hypervisor and loading an entire second OS into memory along with all of its software and data files. At that point I'd say 16GB starts sounding very reasonable.