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ae86_16v · Aug 10, 2003, 05:17 PM

Okay guys, I just got a 512MB for my 867 that originally came with only 256MB.

Now after I installed in the top slot when I click on Apple Profiler it only reads 512MB.

Did I forget to do something?

AssassyN · Aug 10, 2003, 05:19 PM

Whoa...that's weird. Try swapping the 512MB & 256MB chips in different slots and see what it says.

MaxPower2k3 · Aug 10, 2003, 05:32 PM

look on the chip. usually there is a sticker on there with some kind of model number, if not a description. if there's a description, make sure it says 512MB. if there's just a model number, see if the model number says 512 anywhere in it. if not, see if it says 256. i don't think a 512mb stick with only half of the chips working would work at all, so my bet is that they sent you the wrong one.

ae86_16v · 08:27 PM

Originally posted by AssassyN:
Whoa...that's weird. Try swapping the 512MB & 256MB chips in different slots and see what it says.

Max: It does say 512mb for G4Ti.

Assassy: I tried to swap, but the 512 is too big and it won't fit the extra 256 on top.

Shaddim · Aug 10, 2003, 07:13 PM

What does Profiler say when only the 512MB stick is in the machine?

I've seen some pretty strange RAM that doesn't "play" well with others. BTW, if that 512 won't allow you to place other DIMMs in when it's placed in the bottom slot, that generally means it's a low density piece of RAM (the chips sit pretty high up on the PCB). Mixing low and high density memory can cause some strange effects, such as not all the RAM being recognized by the system.

ae86_16v · Aug 10, 2003, 08:27 PM

Originally posted by MacNStein:
What does Profiler say when only the 512MB stick is in the machine?

I've seen some pretty strange RAM that doesn't "play" well with others. BTW, if that 512 won't allow you to place other DIMMs in when it's placed in the bottom slot, that generally means it's a low density piece of RAM (the chips sit pretty high up on the PCB). Mixing low and high density memory can cause some strange effects, such as not all the RAM being recognized by the system.

No, the Profiler said there are two 256 DIMMS.

The guy who sold me this machine had two of these in his powerbook and it showed up as 1GB. So I am guess that it was only meant to be paired with another 512.

I don't know. . .

Shaddim · Aug 11, 2003, 08:10 AM

Originally posted by ae86_16v:
No, the Profiler said there are two 256 DIMMS.

What I meant was Install the 512 stick in by itself and see what profiler says.

The guy who sold me this machine had two of these in his powerbook and it showed up as 1GB. So I am guess that it was only meant to be paired with another 512.

From what you said previously, I'd say that 512 is what is referred to as having "low" density chips, meaning the chips on the DIMM are "thicker" than the chips on your 256MB DIMM (the 256 probably has high density chips). You can't reliably mix DIMMs which have HIGH density chips with DIMMs that have LOW density chips. It'll cause your machine to become unstable and your powerbook won't count all of your memory properly (it'll think your 512 stick is a 256). I've seen this happen several times before.

This is probably the case since you previously said...

Assassy: I tried to swap, but the 512 is too big and it won't fit the extra 256 on top.

Let me know what happens with only the 512 installed, leaving the 256 out. That'll tell me a lot and help me diagnose this.

ae86_16v · Aug 11, 2003, 03:45 PM

Originally posted by MacNStein:

Let me know what happens with only the 512 installed, leaving the 256 out. That'll tell me a lot and help me diagnose this.

Okay, I installed the 512 by itself. So now it is said there is only a 256mb on the lower slot?!?!?!?

I think I forgot to mention, this 512 chip is a bit taller and thicker than the 256 chip. You know how ram has those 4 vertical black things (rectanglar), this 512 has those 4 then then two more that are horizontal on top of the chip.

AssassyN · Aug 11, 2003, 04:17 PM

Originally posted by ae86_16v:
Max: It does say 512mb for G4Ti.

Assassy: I tried to swap, but the 512 is too big and it won't fit the extra 256 on top.

If I'm understanding this right, are you saying the 512MB chip will ONLY fit in one of the two slots due to fitment?

If so, there's an obvious problem as many people have dual 512MB chips in their TiBooks.

ae86_16v · 03:47 AM

Yeah, like I said, the guy that sold it to me had 2 x 512 in there and it fitted fine, but if I were to put the 512 on the lower slot and the 256 on the top, it doesn't fit.

But it'll fit if the 256 was on the bottom and the 512 on top.

carnagex2000 · Aug 11, 2003, 08:02 PM

One thing, I had the same problem with my old B+W Powermac G3, I bought 4x256 pieces of Ram, and they all showed up as 4x128. After contacting Apple, they said that some manufactures RAM will not work properly with Apple/Macs. They said to try using RAM that certified for Apple. Sure enough, I went to Other World Computing and bought 1 stick to test, and amazingly, it worked. (and I borrowed my friends 256 stick from his Desktop G3, which he bought from Crucial, and sure enough, it also worked) So I suggest trying a stick of RAM thats certified to work on Apple. (stay away from cheap RAM)

My two cents worth..

ae86_16v · Aug 13, 2003, 01:52 AM

AssassyN? MacNStein?

AssassyN · Aug 13, 2003, 10:51 AM

Man, I've been pondering this, but I can't help but revert to the obvious; something is either wrong w/ that RAM chip, or something's horribly wrong with your PB. If you're absolutely sure the stick of 512MB you currently possess WORKED in the other guy's PB, yet it'll only fit in ONE of your two RAM slots, there's a definite problem. The major issue is that any compatible 512MB stick should fit in EITHER slot, thus many users having a 2x512MB setup. I'd honestly try to get my cash back and then purchase a 512MB stick through www.coastmemory.com. This is more than just a software issue, this is a physical fitment issue which should definitely not be happening.

ae86_16v · Aug 13, 2003, 03:05 PM

Yeah, the guy said for sure he had two of these sticks and it fitted fine. It is just that I can't fit this 512 on the bottom and the 256 on top, it won't latch down.

When the 512 is on top it is fine.

Like I was saying earlier, when I pop in just the 512, it only reads 256 too.

Maybe I should bring my machine into Emeryville.

israces · Aug 13, 2003, 06:10 PM

Firmware update needed maybe? 4.2.9 needed for certain 512 modules to be recognized

Shaddim · Aug 13, 2003, 06:53 PM

Originally posted by ae86_16v:
Yeah, the guy said for sure he had two of these sticks and it fitted fine. It is just that I can't fit this 512 on the bottom and the 256 on top, it won't latch down.

When the 512 is on top it is fine.

Like I was saying earlier, when I pop in just the 512, it only reads 256 too.

Maybe I should bring my machine into Emeryville.

Sorry, for not getting back sooner.

There's probably something wrong with that DIMM. See if you can swap it for another, and if that fails buy another 512 at some place like CompUSA and test it, keeping the reciept in case you decide to return it.

Graymalkin · Aug 13, 2003, 07:21 PM

Being as the DIMM is so large it is likely dual layer or "low density" RAM. Unfortunately several RAM companies sell you dual layer SODIMMs when they ought to know full well they do not work properly in Macs. Low density chips look like there are a stack of RAM chips on the PCB. Send the chip back for a refund or ask the people to send you a high density chip as a replacement. Typically the low density chips are the cheap ones they sell you out of the bargain bin.

I really don't know why dual layer DIMMs don't work properly with Mac laptops. I seem to recall reading something about low dual layer DIMMs not comforming to all the specifications for SODIMMs and thus they don't work in all laptops. Layering the chips is a cheap way to increase the DIMMs capacity.

ae86_16v · Aug 13, 2003, 09:17 PM

Originally posted by israces:
Firmware update needed maybe? 4.2.9 needed for certain 512 modules to be recognized

Thanks for all the responses.

How do I update the firmware?

israces · Aug 13, 2003, 11:40 PM

Originally posted by ae86_16v:
Thanks for all the responses.

How do I update the firmware?

Now that I look at it some more, I don't think you need to. I think the 867 would have shipped with current firmware as the update I was thinking of was only for 667 and earlier machines. Sorry for any confusion.

On another note, wasn't there a bunch of programs floating around that tested RAM to make sure it was up to Apple standards after the whole 4.1.8 firmware update fiasco? Maybe something like that could help diagnose your problem. Anyone remember these or know where to find a copy of one?

ae86_16v · Aug 17, 2003, 12:28 AM

Okay, so I brought it into the Apple Store. The Mac Genius told me after resetting the firmware, running an hardware test, and taking out and putting in the ram said that it is probably the ram is messed up.

Great!!!

geekwagon · Aug 17, 2003, 01:49 AM

I had this exact same problem with a 12" that I had for a few weeks. I purchased 2 different sticks of 512MB memory from different vendors and they both would come up as 256MB. I never did get that figured out, as I ended up returning it and getting the 17" instead.

Appleman · Aug 17, 2003, 02:27 AM

What about trying this?