Leopard "About This Mac" Memory Info on 12-inch PBG4

[Raging Dufus]

Not a problem, I'm just bored and have a mystery I'd like to solve.

See the images below. On the left is a partial screenshot of the "About This Mac" window from my 12-inch 1.33 GHz PowerBook G4 running Tiger; and on the right is the same info from the same system running Leopard. As you can see, the "Memory" info is reported differently. My question is: why?

I used to think this indicated a problem with the system, but I learned better. I've experienced this anomaly on every 12-inch PowerBook G4 I've owned; which includes not only my current 1.33 GHz but also a 1.0 GHz and two 1.5 GHz models. Diagnostics, testing and experience have confirmed that the discrepancy in reporting memory type has nothing to do with any hardware or software defects - at least, none that I've found. On each of these machines, Tiger's "About This Mac" reports the amount as well as the type of memory, while Leopard's only reports the amount, leaving off the "DDR SDRAM" bit. This occurs regardless of the brand or size of memory module(s) installed. Whatever is causing this seems not to affect System Profiler, which reports the exact same memory info in both Tiger and Leopard.

Seems like I've also seen this on a few 12-inch iBook G4's, which share some hardware with the 12-inch PowerBooks, so I'm thinking there must be something common between the two that causes Leopard's ATM to miss reporting the type of memory installed. I have never encountered this issue on any other type of Mac.

Searching the Internet has been fruitless. Not only have I not found an answer to why this happens, I can't even find where anyone else has mentioned it. It's entirely possible that I'm the only person who cares, but...it...just...bothers me!

Does anybody know why this happens?

 

[redheeler]

256 MB of that 1.25 GB is soldered to the board, so reporting it all as DDR SDRAM is erroneous. I'd assume that is the reason for the change in Leopard.

 

[Raging Dufus]

256 MB of that 1.25 GB is soldered to the board, so reporting it all as DDR SDRAM is erroneous. I'd assume that is the reason for the change in Leopard.

I thought about that, but I don't think it explains the anomalous behavior.

For one thing, the PowerBook's soldered-on 256 MB must also be DDR SDRAM, or else the system couldn't function.

For another thing, iMac G5 iSight models also have soldered-on RAM (albeit DDR2), but do not exhibit this behavior.

 

[redheeler]

I thought about that, but I don't think it explains the anomalous behavior.

For one thing, the PowerBook's soldered-on 256 MB must also be DDR SDRAM, or else the system couldn't function.

For another thing, iMac G5 iSight models also have soldered-on RAM (albeit DDR2), but do not exhibit this behavior.

The built-in RAM isn't reported as DDR SDRAM in the System Profiler (screenshot is from my 12" iBook G4 running Tiger, but also applies to the 12" PowerBook G4s with 256 MB built-in RAM). I don't own an iMac G5 iSight, so I can't confirm if the same is also true for those.

 

[Raging Dufus]

The built-in RAM isn't reported as DDR SDRAM in the System Profiler (screenshot is from my iBook G4 running Tiger).

Thanks for that. Is your iBook a 12-inch, and does it also leave off the "DDR SDRAM" bit in About This Mac?
EDIT: I see that you already said it was a 12-inch. Don't know why my quote left that out? Weird.<

My PowerBook's System Profiler shows the built-in 256 MB in the same way as what you've pictured, in both Tiger and Leopard. But, that doesn't take away from the fact that the built-in memory must also be DDR SDRAM; and also doesn't explain why About This Mac would show the same thing one way in Tiger and a different way in Leopard.

I don't own an iMac G5 iSight, so I can't confirm if the same is also true for those

I don't have an iMac G5 iSight either, but I've had the opportunity to play around with some in the past. Below is a photo I found with a Google image search that seems to confirm my theory:

Would be interesting if someone who owned one of these could take a look at System Profiler and see how it identifies the built-in RAM.

 

[redheeler]

Thanks for that. Is your iBook a 12-inch, and does it also leave off the "DDR SDRAM" bit in About This Mac?
EDIT: I see that you already said it was a 12-inch. Don't know why my quote left that out? Weird.<

My PowerBook's System Profiler shows the built-in 256 MB in the same way as what you've pictured, in both Tiger and Leopard. But, that doesn't take away from the fact that the built-in memory must also be DDR SDRAM; and also doesn't explain why About This Mac would show the same thing one way in Tiger and a different way in Leopard.



I don't have an iMac G5 iSight either, but I've had the opportunity to play around with some in the past. Below is a photo I found with a Google image search that seems to confirm my theory:

View attachment 801109

Would be interesting if someone who owned one of these could take a look at System Profiler and see how it identifies the built-in RAM.

Perhaps it's an intentional code change or bug introduced in Leopard, which didn't apply to the iMac G5 for some reason. But no question it has to do with the soldered RAM.

Found this screenshot of an iMac G5 iSight, using only the 512 MB of soldered RAM:

 

[Raging Dufus]

Found this screenshot of an iMac G5 iSight, using only the 512 MB of soldered RAM

Well, that's weird. Did you notice that the issue is reversed in the iMac? For some reason - at least in the pics that each of us has found - the iMac exhibits the anomaly in Tiger; whereas the PowerBook and iBook do it in Leopard.

I tend to think you're right about it having something to do with the built-in RAM, but - what? And why would it manifest differently in the iMac than in the PB/iB? The plot thickens.

EDIT: Just for giggles, I pulled the 1 GB SODIMM out of my PowerBook, and now Tiger's ATM shows "256 MB Built-in" for memory. Still can't explain why, but at least this proves two things:

1. You're right, @redheeler; and,
2. I really am bored.

Time for me to say goodnight. Thanks for playing!

 

[redheeler]

Well, that's weird. Did you notice that the issue is reversed in the iMac? For some reason - at least in the pics that each of us has found - the iMac exhibits the anomaly in Tiger; whereas the PowerBook and iBook do it in Leopard.

I tend to think you're right about it having something to do with the built-in RAM, but - what? And why would it manifest differently in the iMac than in the PB/iB? The plot thickens.

The iMac G5 About This Mac shows DDR2 SDRAM when something is occupying the slot, and not when only the 512 MB soldered RAM is being used. This appears to be consistent in both Tiger and Leopard, across all the screenshots I saw while doing the search.

So, the Leopard code change only affects the laptop Macs with built-in RAM. Why is anyone's guess.

 

[Project Alice]

I'm curious now, I'll check this out on my two 12" PowerBooks and my 12" iBook G4.