Computer memory

Okay, a question about computer memory: does increasing the memory increase the overall speed of the computer?

If the system runs out of RAM, the overflow is written to the harddrive in the form of a pagefile. When this data is needed again, it must be read back into RAM, which is extremely slow. This manifests as the harddrive churning when you switch between programs or do something memory intensive. If the system has enough RAM, data doesn’t get dumped to the pagefile, so there’s no performance loss. In short, if you have enough RAM, more won’t help anything. If you are running out of RAM, then yes, your system will feel faster with more RAM. Generally, I found that 256MB of RAM is enough for most people. 512MB is more than enough for nearly everyone. Windows95/98/ME support a maximum of 512MB of RAM, Win2k/XP support up to 64GB.

The best way to explain RAM to people that aren’t technical is this:

Okay, picture what you’re trying to load as a bath tub, right now it’s completely empty because nothing has been loaded in there. You have 64mb of RAM, which we can say is equal it about a small cup. As it loads picture you walking back and forth from the the hose to the bath tub trying to slowly fill it. Well, if you upgraded your RAM to 128mb RAM, poof. You get a bigger cup… say a small bucket. Now you can fill your bath tub (load things) faster.

As for it making you’re computer overall faster, short answer… Yes. Long answer, to a certain extent.

Back to the bath tub example to say the long answer. Okay, so you got a bigger bucket now (more RAM), and your walking back and forth, well if you keep getting bigger buckets then eventually the bucket is too big for you too carry, and you can’t even fill it all the way because you can’t carry it when its full. Now, in order for you to speed up filling the bath tub any more than it already is (load stuff faster), you must be able to carry heavier stuff and/or walk faster. Well, think of upgrading you’re processor as making you be able to run instead of walk.

In the end, RAM will make you’re computer faster, but only to a certain point. To get beyond that, you will need to upgrade your processor.

You lost me somewhere. Is the bathtub the ram… or is the bucket the ram? If the ram is the bucket… why are you loading things out of ram into the bathtub?

Anyway… Ram will not make things load faster no matter what you do. More ram will simply allow you to have more loaded at any given time. Loading things quickly (into ram) is a function of how fast your computer can get the program off the hard-drive and to the ram.

I’d go with what Alereon said.

i’ll have a shot at this…

imagine you have a fireplace in your house and a bar counter on the far side of the room. you want to make yourself a drink and the only place you’re willing to have it is on the armchair facing the fire. [ul][li]the problem is the only cup you have in the house is a tiny expresso cup. (that would be your ram, the bottle itself would be the program you’re running) [/li][li]walking to and fro to finish the bottle with that tiny cup is just not done. (a computer with an 8mb ram) [/li][li]had you a bigger cup, things might be acceptable. (128mb ram)[/li][li]but you can always find that bucket (512mb ram) [/li]getting anything bigger would not be necessary, as the bucket is more than enough to contain the bottle.[/ul] better?

Another analogy:

You’re trying to remember a series of phone numbers that are unfamiliar. Once you get past 3 or 4, you’re having to take quick notes on a series of sticky sheets. Wouldn’t it be great to have a bigger memory for this type of thing, so you wouldn’t have to continually write stuff down and go find the next note for the number that’s required now?

Like was said before, though, once you have enough memory for what you’re doing, more won’t help, just like being able to remember 200 numbers is no more help than being able to handle 100, if you’re just working with 50.

Being able to only remember 2, though, could be so frustrating and slow that everything could come crashing down around you.

I think the analogies are pretty good here. (Not that I really know all that much, I am not very technically-minded.)

I’ve tried to explain my somewhat limited understanding of RAM like this: Imagine you have a task to do, and you just have your two hands to get everything done. So you stop and do one thing, go back and do another thing, etc. etc. It will all get done, but it takes a long time.

But if you have a lot of helpers (more pairs of hands, more RAM) then everyone can be simultaniously busy getting the tasks done. This will save a lot of time.

Is that kind of like what it’s like?

Not exactly – your analogy would apply better to processors. I’d say:

Imagine you have a task to do, and you’re sitting at a table, and you can only work on the things directly on the table. On the floor next to you is a box that can hold all of your stuff, but you can’t do anything to the stuff in the box; you have to take it out and put it on the table first. More memory is like having a bigger table – you spend more time working on the actual task at hand, and less time moving things in and out of the box.

Cardinal’s analogy is my favorite for explaining memory. See this thread for a more in-depth explanation of memory and disk space (the two most often confused computer components).

Uhm, I guess I should clarify that I gave the explanation further down; most of the thread is only vaguely related.

Let me give you an example from an earlier era: Macintosh, System 6. (This will help you Windows folks understand things, please follow along)

Macintosh System 6 did not have virtual memory, at all. It had storage space (your hard drive), and it had RAM (the little chips that create a temporary address space). Programs get launched from hard disk into RAM. Your operating system loads at bootup *from * hard disk into RAM. When you save your documents, they go from RAM to hard disk, to make a permanent (until you delete it, that is) copy.

Adding RAM lets you run more programs at one time but it does not make your computer even the slightest, tiniest bit faster.

Now let’s add in the concept of virtual memory. VM comes in handy when you don’t have enough RAM to run Excel and Word and Photoshop and MacWrite and Netscape and Fetch and FileMaker all at the same time. So you upgrade to a newer operating system, System 7. Now, System 7 actually uses up more RAM than System 6 did, so you’d think you would be able to run fewer rather than more programs simultaneously – but System 7 has this new feature where if it runs out of RAM it writes down some of the contents of RAM as if it were a file, saving it to the hard drive in an invisible “swap file”, and then empties up that chunk of RAM and lets you launch another program and put its stuff in the newly-emptied RAM space. Then, let’s say you switch back to the program whose stuff got flushed out of RAM and saved temporarily to the hard disk. The computer has to swap real memory (RAM space) and temporarily-saved-to-disk memory, saving the stuff from the program you’re working on to disk and then reading from disk the stuff from the other program so that it is in RAM and you can work with it.

The tradeoff is speed. The computer can get to instructions and information that is in RAM a whole lot faster than it can get to stuff on its own hard drive. So after installing System 7, you find that you can use more programs at the same time, but that lots of time the computer really bogs down. Well, if you had more RAM, the computer would have do this swap-RAM-info -to-temporary-hard-disk-files routine a lot less often, right? So you go to the store and buy more RAM and your computer is faster now. So to make your computer as fast as possible, you buy all the RAM you figure you need to run all the programs you want to run at the same time, and then you turn off virtual memory entirely and never use it, and your computer is as fast as it was under System 6.

Now, Windows PCs make a much more sophisticated use of virtual memory than Mac System 7 did, and Windows users just never turn off virtual memory because of its efficiency. In fact, if we ignore MacOS X for the following statement, we can say Macs work best if you put a gazillion gigs of RAM in them and turn off virtual memory, while PCs (under Windows at least) work best if you put a moderate amount of RAM in them and let them use their much better virtual memory.

So… to an extent, on a Windows PC, you can add more RAM and, as with the Mac under System 7, it means less swapping back and forth between hard disk and RAM chips, and that speeds up the computer. But once you’ve got enough RAM to minimize the swapping, adding more RAM doesn’t make the computer any faster. If you’ve got an older PC operating system, it may not even like having the extra RAM, even.

“Alright,” said Ford, “imagine this. Right. You get this bath. Right. A large round bath. And it’s made of ebony.”

“Where from?” said Arthur, “Harrods was destroyed by the Vogons.”

“Doesn’t matter.”

“So you keep saying.”



“You get this bath, see? Imagine you’ve got this bath. And it’s
ebony. And it’s conical.”

“Conical?” said Arthur, “What sort of …”

“Shhh!” said Ford. “It’s conical. So what you do is, you see, you
fill it with fine white sand, alright? Or sugar. Fine white sand,
and/or sugar. Anything. Doesn’t matter. Sugar’s fine. And when
it’s full, you pull the plug out … are you listening?”

“I’m listening.”

“You pull the plug out, and it all just twirls away, twirls away
you see, out of the plughole.”

“I see.”

“You don’t see. You don’t see at all. I haven’t got to the clever
bit yet. You want to hear the clever bit?”

“Tell me the clever bit.”

“I’ll tell you the clever bit.”

Ford thought for a moment, trying to remember what the clever bit was.

“The clever bit,” he said, “is this. You film it happening.”


“That’s not the clever bit. This is the clever bit, I remember now that this is the clever bit. The clever bit is that you then thread the film in the projector … backwards!”


“Yes. Threading it backwards is definitely the clever bit. So then, you just sit and watch it, and everything just appears to spiral upwards out of the plughole and fill the bath. See?”

“And that’s how computer memory works, is it?” said Arthur.

“No,” said Ford, “but it’s a marvellous way to relax.”

Thanks, Desmostylus, now I understand perfectly! :slight_smile: