View Full Version : RAM: 768mb to 1gig or 1.5gig?

World Leader Pretend
2006-03-21, 20:33
Sorry for the strange thread title, just following #9 (http://forums.applenova.com/guidelines.html) on the posting guidelines.

I have an iMac G5 1.8GHz, non-iSight, with 786 DDR SDRAM. I tend to run lots of apps at the same time (GarageBand, Gimp, Firefox, Mail, iChat, etc... ) and I frequently check my activity monitor to find that I have only about 9MB of RAM free. The strange thing is is that it never gets below 8MB of free RAM, but the computer starts slowing down anyway.


The solution to this problem as far as I can tell is to buy some more RAM, but how much??

I have the original 256MB stick in one slot, and an upgraded 512MB stick in the other slot.

Should I replace the 256MB stick with a 512MB or a 1024MB stick??

Is there a way to tell how much RAM I actually need to run everything I want smoothly?

I don't want to buy and spend more than I have to.

Please help a RAM starved man!! ;)

2006-03-21, 20:36
might as well go all out with a 1gig, think of the future.

2006-03-21, 20:42
Seems like a no brainer to me. If you're going to upgrade from 768 MB to 1 GB, I don't really see the point of upgrading in the first place. But if you go to 1.5 GB, you'll have double the RAM and your next upgrade (should you want/need to do one) will be meaningful as well.

It would suck if you go to 1 GB now and later you want to go to 2 GB, but you have to ditch BOTH 512 MB modules and sell them at a loss just to do it.

2006-03-21, 20:45
The strange thing is is that it never gets below 8MB of free RAM, but the computer starts slowing down anyway.

Checking free RAM on a Mach-based kernel is useless. Mach always tries to keep 90-100% of the RAM in use. Consider free RAM wasted RAM. It's not a gauge of "I need more RAM" at all.

Is there a way to tell how much RAM I actually need to run everything I want smoothly?

No, there is no accurate way to predict that.

You will want to read these threads: 1 (http://forums.applenova.com/showthread.php?t=12434), 2 (http://forums.applenova.com/showthread.php?t=11247), specifically, since I'm in a conceited mood, these posts of mine: 1 (http://forums.applenova.com/showpost.php?p=280952&postcount=3), 2 (http://forums.applenova.com/showpost.php?p=264375&postcount=12).

2006-03-21, 20:46
1 Gig (total) is fine if you're not doing anything terribly demanding. However, if you're doing a lot of heavy Photoshop work or DVD creation, jumping to 1.5GB might not hurt.

However, keep in mind that you can get a 512MB module for under $40 and a 1GB for under $70. If you ask me, the extra $30 is worth it.

Dorian Gray
2006-03-21, 22:23
What was your uptime at the moment of the screen capture? (Enter "uptime" at a Terminal prompt.) The Process ID number isn't terribly high so perhaps it wasn't that long (depending on your usage patterns), in which case you seem to have a fairly high page out rate, which does indicate that increasing RAM would help performance. That said, at the actual moment of the screenshot you have about 300 MB waiting for serious use ("Inactive"). That 300 MB has been paged to disk so if another app needs the real memory it will instantly be given it. But then when you switch back to the app that originally had that memory, there will be a delay (and disk grinding) while it brings the data into RAM.

"Wired" memory cannot be paged out. "Active" can be paged, but doing so results in an epic performance hit (the kind that results in five minutes of disk grinding during which your computer is basically unusable). (So in your case at the moment of screen capture, if you had less than 93.61 + 356.01 = 450 MB of RAM in your machine you would notice a slowdown so severe that you may think something has broken.) "Inactive" memory can and often will be paged to disk but that isn't always a terrible thing, and does not always manifest itself as an unacceptable performance drop.

It all boils down to the following: more RAM would be a worthwhile investment if your disk is often grinding, as indicated by rapidly increasing page outs in the Activity Monitor.

2006-03-21, 22:53
In general, more RAM = Good!

I have 3.5GB now so speed boosts are pretty minimal now. I don't need more than that very often. (I have a Powermac, but )

2006-03-21, 22:56
I'll just echo what others are saying: if you're going to spring for 512 you might as well part with the extra ~$20 or so and get the gig. Because half the cost of the 512 you're throwing away compared to the 1/4 of the cost of the gig (considering you're chucking 256).

World Leader Pretend
2006-03-23, 01:04
Cool. I think that I should probably future-proof my iMac and go for a gig. This seems like the best investment in the long run.

To answer Dorian Gray's question, I usually have the ram meter circle showing about 9MB of free memory when I am usually working on my iMac. I run Firefox with about 5 tabs-- usually listening to Pandora, iTunes, iPhoto or GarageBand (depending what I'm working on) Gimp, Word, and a few other utilities. I love to use Expose to manage my windows, so I tend to keep a lot of things open at one time.

Does anyone have a certain brand or place to buy RAM for macs at a good price?

I'll check NewEgg, and maybe OWC.

Thanks for the help!

2006-03-23, 12:00
OWC is a nice compromise between quality of service and price. Just make sure that where ever you buy from has a lifetime warranty. Most reputable places do. Use ramseeker.com to give you the lowdown on the cheapest prices.

World Leader Pretend
2006-03-23, 13:34
How does this look? Good? bad?

LINK (http://eshop.macsales.com/item/Other%20World%20Computing/3200DDR1024/)

(Uggh! I'm using a friend's computer with IE, and this site is horrible on it!)

2006-03-23, 14:00
Looks fine. Although you can get Crucial (http://www.newegg.com/Product/Product.asp?Item=N82E16820146545) for about the same price.

World Leader Pretend
2006-03-25, 00:47
Thanks for that link Luca, I'll go with the Crucial stick.

I really like how even a 1.8GHz G5 can run everything I want fast and quickly, Apple is really a great company. Another gig should make my iMac fly! :D