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Discussion Starter · #1 ·
On this site:
http://www.canadacomputers.com/memory.html

Under 168-pin SDRAM, it lists a DIMM 1 GB (1024 MB) in size for $249.00. The question is, does this massive-sized DIMM work in Macs? I know 1 GB DIMMS exist in DDR form, but this is the first I've seen in SDRAM DIMMS. It'd be sweet if my iMac could hold 2 GB maximum. :D
 

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Hey Lars,

I'd really like to know as well! I was told by a few people that the quoted MAX RAM is a specification tested by Apple based on the system. Rumour has that you can push the system beyond that "max"; but I guess there are no guarantees.
I hope someone can offer more insight into this.

Noodleboy.
 

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Discussion Starter · #3 ·
I was told by a few people that the quoted MAX RAM is a specification tested by Apple based on the system. Rumour has that you can push the system beyond that "max"; but I guess there are no guarantees.
I currently run an iMac DV 400 MHz - and the Apple Specification sheet (online at their site) tells me the maxmium RAM it can hold is 512 MB - made up of 2 x 256 MB DIMMS; however, I'm running mine at 640 MB because now there are 512 MB DIMM's available. Buy at the iMac's time of release, 512 MB SDRAM DIMM's didn't exist on the Mac side, therefore making the max RAM on the iMac 3 years ago at its release 512 MB - Apple does NOT update their specification sheets to reflect the change in maxmium possible memory as new DIMM's are released.

The iMac DV does not require Low-Profile DIMM's, therefore I was hoping this 1 GB SDRAM DIMM would work in my iMac; however, whether or not the system based on the iMac's artechiture (sp?) can read it as 1 GB in size is another story. Right now, as most people know it, the iMac DV can hold a maximum of 1 GB of RAM, made up of 2 x 512 MB DIMM's.
 

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I'm looking for that 1G 200 pin chip. I rather make the immediate plunge for it now, as I plan in getting that 12" PB. SInce there only is one slot to play with, trying not to buy a 512 now, only to want to change later. Feel me?? Looked around and I have finally seen the generic 1G chips. No listed price though... will look further.

Since we have the 1G chips for desktops now, will an iMac run 2Gs??? :confused: that could be very interesting..

H!
 

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isnt the max amount of ram locked unless you get a firmware upgrade?
i remember back in my pc days when a motherboard said it would only hold 512megs say that was the max. BUT, when the motherboard company releases a new bios they somewtimes update the amount pf ram you could have.
maybe apple will do this?
 

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So what do you think the chances are of putting a 512 Meg chip in my Tangerine iBook--if it fits, will it work? It's almost worth the cash just to satisfy my curiosity...
 

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Moon hit it. Not sure what the true max is on any of the units. Need to ask around, but we all know that we can run 1G in a Pismo, and the original max was 512.

H!
 

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i have seen new G4 ibook owners talking about putting a 1 gig stick in the ibook. the chips are much too expensive to try this out though. im hoping we'll see a review on the ibooks soon and hear what they havce to say in this subject
 

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I understand that today there are 1 GIG ram chips available and therefore the theororetical RAM totals could go beyond the printed/stated maximum. But, is there not a maximum amount of RAM that Jaguar will see? Or even panther? I'm pretty sure that OS 9 has a system operating RAM limit.

I think the reason that the iMac can run with more than the published total of Ram that Apple states is because you have not exceeded 2 GIGs in TOTAL.

If I'm not mistaken you cannot put 4x1 GIG ram chips in a Quicksilver G4 runnig Jaguar. I believe under Panther it might work, though I'm not possitve. I seem to remember that you have to own a G5 running Panther to go beyond the 2 GIG ram limit. It's a combination of architecture and OS that allows for the new 8 GIG total that we have today.
 

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From an OS point of view:

Yes, OS 9 has a max limit of how much RAM it can see, which is either 1.5 or 2 GB.

MacOS X 10.2.7 and higher (Panther) can obviously recognize at least 8 GB of RAM since the G5's use MacOS X 10.2.7 or higher and you can put 8GB of RAM in a G5. Wasn't MacOS X lower than 10.2.7 limited to 4 GB?
 

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Discussion Starter · #11 ·
I seem to remember that you have to own a G5 running Panther to go beyond the 2 GIG ram limit.
That is correct - only the Power Mac G5's can see/use more than 2 GB of RAM - the G4's can see a maximum of 2 GB of RAM (MDD models only), while all non-MDD G4 models can see/use a maximum of 1.5 GB of RAM (despite if you put 4 x 512 MB chips in your Quicksiliver, etc - 1.5 GB is maximum in those models).

MacOS X 10.2.7 and higher (Panther) can obviously recognize at least 8 GB of RAM since the G5's use MacOS X 10.2.7 or higher and you can put 8GB of RAM in a G5. Wasn't MacOS X lower than 10.2.7 limited to 4 GB?
See above. It's not just the OS (Panther) that allows for the maximum RAM limit. Older G4's who run Panther can not use 4 GB of RAM, or more than 2 GB for tha matter (1.5 GB max for non-MDD G4 models) just because they now run Panther.
 

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Discussion Starter · #12 ·
Although my iMac under both OS's (Mac OS X v10.3 Panther and OS 9.2.2) can use up to 1.5 GB of memory, I wouldn't be restricted by my operating system to use 1 GB SDRAM DIMM's, but if I am restricted from using such large sized RAM DIMM's, it would be because my logic board in the iMac does not support such large RAM DIMM's - not that the operating system can't use that much RAM. It would most likely be a hardware limiting factor.
 

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Interesting

Just for the record, my old Yikes G4 could only hold 1 GB of RAM as there were 4 slots and each would only recognise 256 MG chips. 512's didn't work.

farfisa: If that doesn't work in your iBook, let me know, I might be able to use it in mine.
 

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Discussion Starter · #14 ·
Just for the record, my old Yikes G4 could only hold 1 GB of RAM as there were 4 slots and each would only recognise 256 MG chips. 512's didn't work.
The 1.5 GB limit applies to Sawtooth G4's or better. The "Yikes" G4 simply had a Blue and White G3 logic board.
 

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First of all, Apple's RAM specs are based on testing the highest density modules available when the Mac was current; ie when the specification is finalized shorty before that model goes on sale.

If higher density chips come out later, they may work but Apple never revises the spec to reflect that (revisions may happen if there's a newer, but similar model released, but the spec sheets are written in stone once a Mac model ships).

So, there are many cases where a given model can handle more RAM than the spec.

" ... i remember back in my pc days when a motherboard said it would only hold 512megs say that was the max. ..."
PC memory data is written in the BIOS, so a firmware upgrade is often required to use higher density chips. Macs don't have a BIOS chip, or anything like a BIOS chip, so that limitation doesn't apply. But there are other hardware limits that effectively do limit maximum RAM.

The Operating System has limits on how much memory it can address. For example, OS9 cannot "see" memory beyond 1.5GB, while any one individual program running under OS9 can use a maximum of 1GB (actually just a tiny bit under 1 gig).

So, there are both hardware and software (OS and application) limits as to how dense a RAM chip can be, how many you can stick in there, and how much the System can use if they do physically & electrically fit in there.

When memory manufacturers introduce higher-density chips, it's best to believe what they say regarding compatibility, because they're the guys who make or lose money based on this information, and will test it on a model-by-model basis. Guessing or thinking it "should" work is not a reliable method.

Someone mentioned QuickSilver Macs; I have one. It has 3 RAM slots for a maximum of 1.5GB. Now, OSX can handle 2GB no problem. Would filling 2 slots with 1Gig sticks work? Maybe, maybe not. Buy from a reputable vendor and you shouldn't have to worry.

Some old-timers might remember "SIMM Doublers"; these were RAM-like boards that plugged into a RAM slot, but allowed you to plug 2 sticks into the board. So, if the higest density SIMM was 16MB but the system could handle 32MB per slot, you could exceed the physical limit that way. But they only worked in some models that had the "room" in both hardware & software to accomodate them.

Memory is the most transistor-count intensive product for a computer; there are many, many more transistors squeezed into an 8MB memory chip than there will be in any CPU you can buy today from any manufacturer. So increasing the density is not a trivial matter.

Why chips must be made denser is revealed when you learn that of all the pins on a modern DDR SDRAM module, only 16 can be used to move data in and out. This means that a minimum of 4 chips are needed to use a 64-bit memory bus (16 bits per chip) like those found in modern PCs and G4 Macs. This also explains why you need 2 RAM modules to accomodate the G5's 128MB bus.

The only way to physically fit all those chips on the board is to make them denser (everything is smaller and closer together).

As such, we're dealing with the absolute state-of-the-art with regard to fabrication; high rejection rates; and low volume sales. Read: expensive.

For RAM chip fabrication, there's a technology limit on how dense you can make them, and a physical limit on how big they can be and still fit on the card.

[ November 05, 2003, 06:23 PM: Message edited by: gordguide ]
 

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Okay, so obviously I was in the mood for a mission. I went to Canada Computers on College (a short walk, actually) and picked up a 512 Meg chip, and replaced the 128 Meg chip that was in there (which I paid $400 for three and a half years ago--ouch).

The first time I installed it it didn't work--the caps lock and num lock LEDs wouldn't go off and the keyboard didn't respond. I thought the RAM might have been too fast (I know the bus is only 66). I took it out and put it back in, and lo and behold it works!

So now I'm up to 544 MB in an iBook 300. It's still pretty much a toy, but it also has a 30 Gig drive (now putting THAT in was a heart-stopper) and it's running 10.3, so it's gotta be pretty much the hottest Rev. A. iBook out there.

Four posts and I've already experimented with my iBook... this place is dangerous.
 

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Discussion Starter · #17 ·
So now I'm up to 544 MB in an iBook 300. It's still pretty much a toy, but it also has a 30 Gig drive (now putting THAT in was a heart-stopper) and it's running 10.3, so it's gotta be pretty much the hottest Rev. A. iBook out there.
Hot! Hot! We know this works now! Now I really want a 1 GB DIMM for my iMac.. not that this will work automatically just because the iBook had luck, but this is good news indeed. \

CubaMark, now your iBook can have more RAM. ;)
 

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awesome farfisa

PC memory data is written in the BIOS, so a firmware upgrade is often required to use higher density chips. Macs don't have a BIOS chip, or anything like a BIOS chip, so that limitation doesn't apply. But there are other hardware limits that effectively do limit maximum RAM
"i did not know that. i find that quite wild"
 

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In the past when I have upgraded my RAM (going back 3 or 4 years) in a B&W G3 or my Quicksilver 733 or even my 867 dual MDD, I purchased generic PC RAM from a PC store on College street here in Toronto. The RAM at this store is always incredibly cheap compared to an Apple authorised reseller. But, I've noticed that in the past 9 months that Apple resellers are now selling RAM at prices that are almost the same as the PC stores. Anyone know why it took so long for the Apple resellers to finally get their prices down to almost the same level as PC users? Is name brand RAM a far supperior product than generic RAM? I know that there are different voltages for the same kinds and sizes but what other factors are affecting the price?

The generic PC RAM that I bought over the years always worked every time. I even upgraded my friends powermacs with RAM from the same PC store all the time. I have probably bought over 25 to 30 generic chips from the PC store over a 4 year period.

Does anyone know 100% for sure if I can use any old generic RAM chip in my new G5 1.6 gHz or do I have to be extra careful now with the new powermacs? I currently have 4 slots available and have installed 2x128 meg & 2x512 meg chips. I want to remove the 2x128s and replace them with new 2x512 megs. I want to get the RAM but at the best value for my money.

I have read that the more RAM that the G5s have installed the better the performance that you will have with them. Does this theory apply to every RAM upgrade? Or just the first time a G5 surpases 1 GIG in total? I'm only talking about the perfomance of the G5 in running one application at a time and NOT photoshop. I know that photoshop loves RAM. Is it an OS X issue? IS OS X needing more than say 512 megs of RAM to run optimally?

Lots of questions here, anyone know some of the answers?

Cheers!
 

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First off, thanks to Lars and moonsocket for the virtual pats on the back. I don't use my iBook for much, but totally wanted a new one anyway (I don't think I have to explain that to anyone here!), but recently with Jaguar and now Panther, it's like it's getting younger. And now with the RAM boost, I might actually try some hard-core apps!

Now as for the Generic RAM issue, I've been wondering about that too.
I found this site online which has this "Memory configurator" and I played with it a bit (I'm planning on getting a G5 v. soon and also thought of the RAM question):
It's memorysuppliers.com.
Right in the middle of the main page there's this blue box. It lets you select your computer from pulldown menus, and finds out what 'brand' of RAM is "guaranteed compatible" with your system (of course I wouldn't be writing this post if it didn't include Mac hardware in the lists). Then of course you say thanks, walk away and find the closest dealer with the same RAM at the lowest price...

So for Timothy J's PowerMac G5 1.6, it recommends pairs of SAMSUNG 512MB PC2700 DDR333 6NS CL2.5 DDR SDRAM.
I know Canada Computers (on College) has the Samsung PC-3200 DDR400 chips (for the 1.8 and Dual 2 G5's), for $128 apiece, but it doesn't have the PC2700 listed.

They do have the appropriate KingMax RAM ($118 / stick), though, and KingMax has a bunch of references to Mac on their site (I just put some of their RAM in my iBook too).

Anyone know who Apple buys their RAM from? Maybe Samsung? Anyway, probably not a "Mac-only" RAM-maker, but that's just guessing.
 
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