RAM upgrade 320MB>576MB - will I notice the difference?

[JazzDude]

Hi,

I'd like to upgrade the RAM on my iBook500 CD. It currently has 320MB (64+256) installed and I'll probably order another 512MB. Two questions:
• will I notice an improvement, performance-wise (running 10.1.2)?
• can I install the 256MB module from my iBook in my iMac Rev.B (any slot)?

Thanks,
Tommie

[griffman]

It probably depends :-). What do you run on the iBook? We have 256mb on ours, and it's been more than sufficient for the basics -- I can run Word, Excel, a couple of browsers, iTunes and a few other miscellaneous programs without any side effects. What do you use your iBook for?

As for the "can you use in the iMac..." question, that's probably best answered by one of the experts at the Mac memory places -- they could tell you in a half-second.

-rob.

[JazzDude]

I run the Office apps, ICQ, one or two browsers, a Carracho Server, TextEdit, SystemPrefs and Terminal (always open)... with those apps open, I see quite a few page-ins in "top". I also get the spinning beachball cursor a little too often for my taste, especially when switching to an app that was in the background for a while. Booting up takes close to 2 minutes, which is way longer than any PC I've seen...
Oh, and I've got a FW-HD attached to the iBook most of the time.

I read in another forum (forgot where) that upping the RAM above 512 doesn't do much (at least on a G4)... can anyone confirm this on a G3?

[Phil St. Romain]

I upped the RAM on my G3 Firewire Powerbook from 256 to 640 and I didn't really notice much of a difference on speed until I did some pretty heavy multi-tasking, then the extra RAM seeemed to make everything run smoother.

[Craig R. Arko]

Updating from 320 to 640 was a blessing for me; I can now run Classic, VPC, and XDarwin simultaneously without generating any additional swap files.

[dbhill]

I do some memory intensive work and noticed a huge difference going from 256 to 512. But the difference was just noticeable from 512 to 1028. Not sorry to have a gig of RAM, still get pageouts occassionally, but it's tolerable.

~Dennis

[noxioux]

Your ibook ram will probably not work on your imac. Your imac will have two DIMM slots for PC100 or PC133, and just about any DIMM will work. I've tested several, and I currently run 384mb on my imac. Upping your RAM is really the single most effective thing you can do to enhance your computer's performance. Here's how to check to see what types your computers run for sure:

In each computer go to the apple menu and down to the Apple System Profiler. Look for the memory overview, and it will tell you the location, size and memory type. If they match (they shouldn't), then the swap would be fine. I am all but certain that they are very, very different.

[mervTormel]

you will always have some page-in activity, and that's normal

it's page-outs that indicate you've crossed the line

page-outs are the kernels way of saying, "Hey, i've run out of memory, and now, something has to go. hmmmm, the oldest accessed pages are a candidate, let's look at those... yep, flush you suckers."

this is when everything comes to a pretty much dead halt while the kernel, in a somewhat panicy mode, tries to free up memory for a request. now you're hitting disk, not the page cache (page-ins).

once you start page-outs, theres little to be done except quit memory hogs and let the pager/swapper acquiesce (wipe its brow, have some tea).

i use memory monitor (see versiontracker) and it's great. i can see the free memory creep to near zero, which alerts me that i'm gonna start swapping out pages, so let's quit some processes that were left stagnant.

as for more memory making a difference, the number one rule on a virtual memory system: more memory = better performance overall

memory don't make your processor faster, that's a myth. it won't make your calculator launch any faster, or multiply faster. it just forstalls the inevitability of page-outs as you work with many apps.

cheers

b

[JazzDude]

Firstly, thanks for all the replies so far. Today I installed a 512MB module in place of the 256 (which I still plan to put in the old iMac as it looks almost exactly the same as an old 32MB module from that same iMac). Installation was easy, took only a couple of minutes. Is my iBook faster now? No. It's just that I don't get that spinning beach ball as often. I currently have 16 apps (including the whole Office suite) plus a few background processes open and have yet to get a pageout. Cool!:) I encourage everyone to max out their Macs (n.p.i.) if they can afford it. It lets everything run quite a bit smoother.

One more question about the RAM compatibility: is it possible that the 256MB module from the iBook won't work in the iMac even if it physically fits?

[mervTormel]

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One more question about the RAM compatibility: is it possible that the 256MB module from the iBook won't work in the iMac even if it physically fits?

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this is definitely prohibitive. i would be nervouser than a long tailed cat in a room full of rocking chairs.

you could fry your iron, or blow a whole in the space-time continuum.

[JazzDude]

...what might happen if I dared to pop the allegedly incompatible RAM in that old machine of mine? Y'know, I'd hate to have that thing (the 256MB module) uselessly lying around....

[mervTormel]

Originally posted by JazzDude
...what might happen if I dared to pop the allegedly incompatible RAM in that old machine of mine? Y'know, I'd hate to have that thing (the 256MB module) uselessly lying around....


fry your iron = burn you biscuits = toast your board

it may just boot to sad mac and make a crash sound, or some other unpleastant tone or experience.

but it may melt, also. check the specs at one of the ram tracking web sites. you may get a better idea about the compatibility of that ram.

i just don't know

lest us know if you survive.

[griffman]

I'm going to move this one to the "Hardware and Peripherals" forum, as it's not really an OS X experiences thread.

Thanks to the nice forum software, though, you'll see that it's been moved instead of having to go hunt for it!

So please, carry on!

-rob.

[davidro]

Is this your machine?
<http://www.info.apple.com/info.apple.com/applespec/applespec.taf?RID=285>

iMac, 5 flavors, 266mhz?

It uses SO-DIMMS, but is "limited" to 128Mb in each slot. I have found in the past that you can usually go one step above what Apple reccomends. ie. try the 256!

As for adding RAM, I have found that the more you have the better! My dad's iBook is maxed out now (640mb) and performance is notceably faster than when he had only 384MB.

cheers!

dAVE

[JazzDude]

Actually, it's the 233 MHz version, but the RAM type is just the same. I'll try it.

[JazzDude]

Today I decided it's time to dare... I popped the 256 module in the upper RAM slot of my Rev.B BondiBlue iMac (233MHz). Guess what? I didn't fry the board. But only 128MB of that module is recognized :( Does anybody know how to change that?

[davidro]

I do not know of a way to change the limit on memory that can be installed. I think it is actually set in the hardware somewhere...

Maybe you can trade the 256 for 2 x 128's?

cheers,

dAVE

[mervTormel]

that other 128MB dropped thru that wormhole you created :D