PowerPC Mac G4 - Ram help!

[mattriz]

Hello! I recently bought at a car boot (market) an iMac G4, version M6498. It's the 800mhz version. It's lovely, but dead slow as it only had 256mb of ram in it.

I'm struggling to find some good, cheap and compatible ram on the UK ebay.

Can anyone help? I'm really not sure exactly what Ram it should have. I'm after ideally 1gb SO Dimm so the smaller ram to fit in the user assessable slot.

Thanks in advance!

Matt

 

[eyoungren]

Paging @LightBulbFun Please pickup the white courtesy phone!

 

[mattriz]

Paging @LightBulbFun Please pickup the white courtesy phone!

Here's a pic of the slot, if that helps?

 

[LightBulbFun]

Max RAM for that iMac model is 1GB

via 1 512MB PC100 (or PC133) SODIMM and 1 PC100(PC133) Desktop DIMM in the inside slot

remember if you do open it up to replace the internal DIMM MAKE SURE you re-paste the thermal contact point between the CPU heat pipe and the dome failure to do so WILL fry the CPU.

 

[mattriz]

Thanks for your help, much appreciated
[doublepost=1536854424][/doublepost]

Max RAM for that iMac model is 1GB

via 1 512MB PC100 (or PC133) SODIMM and 1 PC100(PC133) Desktop DIMM in the inside slot

remember if you do open it up to replace the internal DIMM MAKE SURE you re-paste the thermal contact point between the CPU heat pipe and the dome failure to do so WILL fry the CPU.

Is it possible to get a 1gb version of that ram, or do I have to get two 512mb rams?

 

[LightBulbFun]

Thanks for your help, much appreciated
[doublepost=1536854424][/doublepost]

Is it possible to get a 1gb version of that ram, or do I have to get two 512mb rams?

there are no 1GB PCxxx SODIMMs sadly so to get to 1GB you need 512x2.

plus AFAIK the Pangaea chipset does not support 1GB DIMMs

 

[Eriamjh1138@DAN]

How can any current PPC owner not know of everymac.com? It’s where I go for specs.

 

[dbdjre0143]

How can any current PPC owner not know of everymac.com? It’s where I go for specs.

Probably the same way we all didn't know until someone told us or we read it somewhere like here. Still, totally agree its a great (albeit not infallible) resource.

 

[torvan]

there are no 1GB PCxxx SODIMMs sadly so to get to 1GB you need 512x2.

plus AFAIK the Pangaea chipset does not support 1GB DIMMs

Actually, there are 1 GB SODIMMS. I just installed one in my G4 1.25Ghz USB2.0 iMac and it works like a charm. The Amazon link: https://www.amazon.com/gp/product/B003CH5346/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1.

I know it is not the same machine as mine--but just wanted to show that they are made and can be bought.


View attachment 783084

 

[LightBulbFun]

Actually, there are 1 GB SODIMMS. I just installed one in my G4 1.25Ghz USB2.0 iMac and it works like a charm. The Amazon link: https://www.amazon.com/gp/product/B003CH5346/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1.

I know it is not the same machine as mine--but just wanted to show that they are made and can be bought.


View attachment 783084

and my MacBook Pro has 2 8GB DDR3 SODIMMs whats your point?

we where talking about PC SDRAM

your machine takes DDR SDRAM which is not relevant to what we where talking about.

 

[AphoticD]

AFAIK, there were no 1GB memory modules in the PC100/PC133 spec which is what the OP's iMac appears to use (as per @LightBulbFun initial reply). However, later model iMac G4s 1GHz or faster (like @torvan 's iMac) used PC2100 or PC2700 RAM which was available in the 1GB capacity. IIRC, PC2700 modules were also compatible with models spec'ed for PC2100 and would simply clock down.

The PC2100/PC2700 and PC3200 memory used in the iMac G4 and Power Mac G5 and iMac G5s (prior to the '05 DDR2 models) all maxed out at 1GB per module.

The DDR2 RAM in the late '05 Power Mac and "iSight" iMac G5 maxed out at 2GB per module... However, 4GB modules were available and I believe may have been usable in a Quad or Dual Core, but the OS was limited to 16GB maximum memory, regardless of the machines being able to take 8x 4GB modules.

 

[z970]

via 1 512MB PC100 (or PC133) SODIMM and 1 PC100(PC133) Desktop DIMM in the inside slot

Didn't Apple say not to use PC100 DIMMs with that model?

remember if you do open it up to replace the internal DIMM MAKE SURE you re-paste the thermal contact point between the CPU heat pipe and the dome failure to do so WILL fry the CPU.

Nice to know. A little while ago, I came very close to taking that stuff off, not entirely knowing what it was.

Disaster (inadvertently) averted.

Hey, can you tell me why in God's name they put a plastic sheet over the G4 CPU inside the computer? The damn thing makes it very hard to repaste it without screwing everything up. I almost took that off, too.

 

[mode11]

When buying PC133 for G4 Macs, make sure it's *low-density* RAM. I've had 'fun' recently finding suitable DIMMs for Macs of this era. Most of the eBay sellers don't mention it in listings, since PCs were generally happy with either sort (high or low density).

Good guide here, with suitable model numbers to search for at the bottom. I had to search worldwide on eBay to get suitable RAM at a sensible price. Kingston Value RAM (KVR- prefix) is often suitable, though pay attention to precise model numbers.

 

[LightBulbFun]

When buying PC133 for G4 Macs, make sure it's *low-density* RAM. I've had 'fun' recently finding suitable DIMMs for Macs of this era. Most of the eBay sellers don't mention it in listings, since PCs were generally happy with either sort (high or low density).

Good guide here, with suitable model numbers to search for at the bottom. I had to search worldwide on eBay to get suitable RAM at a sensible price. Kingston Value RAM (KVR- prefix) is often suitable, though pay attention to precise model numbers.

in terms of PowerPC macs

Uninorth (1, 1.5, 2, 3, 4, Pangea and intrepid/2) based Macintosh computers dont care about Memory density

you only have to worry about Memory density on Grackle (MPC106) based Macintoshes.

 

[mode11]

Do you have a source for this? Everything I've seen online suggests the SDR G4's prefer low-density.

As you say, it's definitely the case with Grackle-based machines (G3, G4-Yikes). I've had first-hand experience of this recently with a G3 iMac and G3 Clamshell iBook.

Fitting a high-density PC133 module to the G3 iBook resulted in only half of its capacity being seen (as is often the case); a G4 Titanium wouldn't even boot with it in. The G4 works fine with low-density RAM. I guess there could be something else about the DIMM it didn't like, though.

 

[LightBulbFun]

Do you have a source for this? Everything I've seen online suggests the SDR G4's prefer low-density.

As you say, it's definitely the case with Grackle-based machines (G3, G4-Yikes). I've had first-hand experience of this recently with a G3 iMac and G3 Clamshell iBook.

Fitting a high-density PC133 module to the G3 iBook resulted in only half of its capacity being seen (as is often the case); a G4 Titanium wouldn't even boot with it in. The G4 works fine with low-density RAM. I guess there could be something else about the DIMM it didn't like, though.

my Source is the fact I have several High density SDRAM PCxxx sticks working fine in a few of my PowerMacs/PowerBooks etc. and from other people doing the same.

the case you mention was that with just 1 stick or multiple sticks tried in the same machines? @AphoticD had a 512MB RAM stick that was bad, so I recommended he use it one of his Grackle machines where it would be seen at half capacity and hope that the bad RAM is in the upper 256MB. (which IIRC it was )

so it may be a case of just a Bad RAM stick.

 

[mode11]

Good to know, would certainly save hassle buying RAM for G4s. Is there any particular brand of RAM you use, or is it random?

Perhaps the low density thing is a red herring in the case of G4s, though I've had RAM weirdness in other ways e.g. certain combinations of sticks working in machines, or working in one machine but not another. All the sticks I have are 512MB PC133. Maybe it comes down to SPD entries. The low density stuff always seems to work.

From what you said, it sounds like the RAM stick is just duff (i.e. iBook sees the working half of it, but it fails POST in the G4). Unfortunately I only had one laptop (a G3) to test it in at the time, so difficult to prove it was faulty.

 

[bunnspecial]

My GENERAL rule of thumb(since I lack @LightBulbFun 's encyclopaedic knowledge of PPC chipsets) for PPC Macs is that I use LD RAM when using the largest capacity modules that a particular model supports.

That means that my beige G3s, B&Ws, and Yikes! all get LD 256mb modules, while my AGP-based towers that take SDRAM get LD 512mb sticks.

HD 256mb sticks, for example, have never been an issue for me in something like a Quicksilver...although I don't really have that much use for HD 256mb sticks as I'd rather put 512mb sticks in those.

A while back, I ordered I think 20 256mb PC-133 sticks that were advertised as low density, and they arrived from China as high density. The seller refunded me and said "don't worry about sending them back"-and I reordered from a different seller and made sure I actually got LD sticks. Some of those ended up scattered in various DAs/QSs/Sawtooths(Sawteeth?)/GigEs(or the never used code names-Snakebite or Medusa). The rest ended up getting tossed in when I shipped @LightBulbFun a couple of pounds of RAM.