11-01-2008, 12:39 PM

New to the forum and have just moved to a MAC from a pc. I have previously upgraded my Power Mac G5 model PowerMac7,3 from 1GB to 3GB ram with no problem.

I was under the impression that I could upgrade my ram upto 8gb (2X2GB+2X2GB)
So I bought a pair of 1GB ram sticks to work alongside another pair of 1GB sticks. Everything runs fine it is just that the about this mac stats shows only 3GB of ram and X2 1GB sticks are noted as a pair of 512mb.

If I mix them around the machine runs fine but registers the ports j11 and j12 as 512Mb

Why is this?

Please be kind I am on a very steep learning curve with a fragile ego.

Also any advice of what to do about the 2X1GB of ram I have just bought and appear to have no use for.

Thanks
Zac

11-01-2008, 12:57 PM

Quite simply, your machine does not recorgnise that much ram

Only 64 but capable systems can see that much ram which includes some G5 and Intel Systems

For more info see this article

AppleInsider | Road to Mac OS X Snow Leopard: 64-bits, Santa Rosa, and more

11-01-2008, 06:49 PM

what are the specifications for the ram you had just installed?

11-03-2008, 08:15 AM

Louishen I was afraid you were going to say that

Powermac G5 my spec are

Machine Name: Power Mac G5
Machine Model: PowerMac7,3
CPU Type: PowerPC G5 (2.2)
Number Of CPUs: 2
CPU Speed: 1.8 GHz
L2 Cache (per CPU): 512 KB
Memory: 3 GB
Bus Speed: 900 MHz
Boot ROM Version: 5.1.8f7

Hopefully this changes everything. If not is there anything I can do?

11-03-2008, 09:01 AM

that is a 64-bit system...I have one just like it upstairs! I have 3GB of RAM in mine and it should hold up to 8GB like you thought. There might be something wrong with the RAM. Can you give us the specs of the RAM that is not recognizing correctly?

11-03-2008, 10:44 AM

All the ram sticks are 1GB and even if I change them around the following is listed:
J11+J12
Size: 512 MB
Type: DDR SDRAM
Speed: PC3200U-30330
Status: OK
J13+J14
Size: 1 GB
Type: DDR SDRAM
Speed: PC3200U-30330
Status: OK

This leads me to think that the stick are fine. Its just that my mac will not do more than this?

However any advice would be great.

thanks
Zac

11-09-2008, 01:11 AM

Yes, all G5's are 64 bit. On my measly 1.6ghz, the paired sockets aren't actually the two that are right next to each other. It goes like this

- 1
- 3

- 4
- 2

[the dashes are the ram slots the way the are laid out]
So when you pair the ram type, size and speeds the two that are the same would have to go in 1 and 2 and the other two that are the same would go in 3 and 4. But, mine aren't layed out what you'd think they'd be. So maybe you should mess around with that? Are all four of your sticks the EXACT same brand, speed and size? G5's are very picky.

11-21-2008, 01:33 PM

Thanks for that. All the sticks are the same speed and siize but not the same brand. Have paired brands together. Alas still the same.

I will have to by another G5 in January for editing so will make sure I get a more upto date model that can be made to be faster than and use the remaining 1GB sticks I have lying about.