RAM Problems/horror stories in Dual 867MHz G4 Tower

[thomasp]

Hi,

We have a Dual 867MHz G4 (MDD) which currently has 1.75Gb RAM, and we were hoping to upgrade it to 2Gb.

Currently, according to Apple System Profiler, Slot 0 (nearest the processors) has a 256Mb chip in it, slots 1, 2 and 3 (3 nearest graphics card) have 512Mb chips in them. This was confirmed with a "visual inspection" (well, more taking the 256Mb chip out and reading the label on it)

We ordered a 512Mb Integral chip (PC2100, DDR, 184pins, etc, etc, etc) from Computer Warehouse - a respectable company who we've ordered many comptuers and software from before.

On installing the chip, there was no label on it saying how "big" it was - this was the same as the three 512's already in the G4. We installed it in slot 0 - occupied by the 256Mb chip.

We checked the new chip was seated properly and started the G4 up. The Apple System profiler said there was still 1.75Gb of RAM in - exactly the same as before. And, slot 0 was still filled with a 256Mb chip.

I then put the supposed 512Mb chip into bay 3 (putting the old 512Mb aside) and left bay 0 empty. Booting up again showed that bay 0 was empty and bay 3 had a 256Mb chip in it.


We phoned Computer Warehouse up, and they checked the number on a sticker on the new chip of RAM (a production code, which matched one of the other 512Mb chips....) and they confirmed it was a 512Mb chip... Very strange, since out faithful mac though otherwise...


Anyone have any ideas why a company and a computer can disagree on how big a stick of RAM is? After checking on the CW website, they don't even list a 184pin 256Mb chip of RAM by Integral.

Who should we believe? A computer (albeit a mac!) or a human reading data off a Mac (at the other end of a phone)?

 

[yenko]

Hi,

We have a Dual 867MHz G4 (MDD) which currently has 1.75Gb RAM, and we were hoping to upgrade it to 2Gb.

Currently, according to Apple System Profiler, Slot 0 (nearest the processors) has a 256Mb chip in it, slots 1, 2 and 3 (3 nearest graphics card) have 512Mb chips in them. This was confirmed with a "visual inspection" (well, more taking the 256Mb chip out and reading the label on it)

We ordered a 512Mb Integral chip (PC2100, DDR, 184pins, etc, etc, etc) from Computer Warehouse - a respectable company who we've ordered many comptuers and software from before.

On installing the chip, there was no label on it saying how "big" it was - this was the same as the three 512's already in the G4. We installed it in slot 0 - occupied by the 256Mb chip.

We checked the new chip was seated properly and started the G4 up. The Apple System profiler said there was still 1.75Gb of RAM in - exactly the same as before. And, slot 0 was still filled with a 256Mb chip.

I then put the supposed 512Mb chip into bay 3 (putting the old 512Mb aside) and left bay 0 empty. Booting up again showed that bay 0 was empty and bay 3 had a 256Mb chip in it.


We phoned Computer Warehouse up, and they checked the number on a sticker on the new chip of RAM (a production code, which matched one of the other 512Mb chips....) and they confirmed it was a 512Mb chip... Very strange, since out faithful mac though otherwise...


Anyone have any ideas why a company and a computer can disagree on how big a stick of RAM is? After checking on the CW website, they don't even list a 184pin 256Mb chip of RAM by Integral.

Who should we believe? A computer (albeit a mac!) or a human reading data off a Mac (at the other end of a phone)?

Just guessing from the description you gave that MAYBE you have the wrong type of RAM installed on that machine. I believe it takes SDRAM...NOT DDR.....PC133 SDRAM.

May want to check with Crucial Ram website for the correct RAM.

 

[cubist]

I've had problems before like this, where the organization of the bits on the memory was wrong. Does the support page for that RAM say it supports the G4 MDD? If not, it may work as 512MB in another system but not in yours.

 

[simie]

Can you test the ram in another computer. Stick it in a pc, as you soon be informed by the PC's bios if the ram is 512 or just another 256 mb stick.

The company should exchange it if its faulty as it under warranty.

Power Mac Ram Chart

 

[thomasp]

According to the webpage that we ordered it from on CWOnline, it was specifically for the Dual 867MHz G4's, and I double-checked on Crucial.com (before ordering) and triple-checked in the G4's manual...

The only thing is the RAM packet says it is 266MHz, but the G4 manual says use 167Mhz RAM - could this be a problem?

We can't check it in another computer. We have a G3 desktop (won't accept 512's), a G3 iMac (won't accept DDR RAM, and probably not 184pins) an iBook and a PowerBook. These are the only computers we have.

To quote from this webpage, where we bought the RAM: http://www.cwonline.co.uk/details.t...=details&listing=subcategories&nocache=621637

This memory fits the new Apple Xserve and the NEW G4 Dual 867Mhz model only!

Anyway, we've posted the chip back to Computer Warehouse, but that was the last one they had in stock.

Is Integral RAM generally quite good?

Is it possible to "blow up" 256 Megabytes of memory through static, but still leave 256Mb working fine (I don't think static is a problem in this case)? I'd have thought that if the chip had been blown up by static, it wouldn't work at all.

 

[mchendricks]

RAm for MDD 867

I have the MDD 867 as well. I know that the computer takes DDR 2100 RAM chips. It will also accept PC 2700 DDR RAM since I've had that in the computer. The FSB is 133 MHz, not 167 MHz. I have a 256 MB chip in slot 0, but can move a 512 MB chip from slot 2 to verify that slot 0 will take the 512 MB chip if you want.

Mike

 

[yenko]

I have the MDD 867 as well. I know that the computer takes DDR 2100 RAM chips. It will also accept PC 3700 DDR RAM since I've had that in the computer. The FSB is 133 MHz, not 167 MHz. I have a 256 MB chip in slot 0, but can move a 512 MB chip from slot 2 to verify that slot 0 will take the 512 MB chip if you want.

Mike

OOOps. Must have hit the wrong search key or brain-farted in my original response to this post.

Sorry I gave the wrong info there, everybody.

 

[ReanimationLP]

Is the RAM single sided or double sided? If its single sided, then theres your problem.

 

[thomasp]

Is the RAM single sided or double sided? If its single sided, then theres your problem.

What do you mean by that?

Do you mean it only has IC's on one side?

 

[simie]

If the stick of 512 mb is single sided then it will only have chips on one side as the other side will be blank.

 

[thomasp]

If the stick of 512 mb is single sided then it will only have chips on one side as the other side will be blank.

We've sent the stick back now, but from what I can remember, it definately had chips down both sides.