RAM problem

[Ogre55]

I have a 1.33 ibook and just installed what was suppose to be a 1 gig RAM chip. My computer tells me I have 768 megs of RAM now. I took the chip out and looked and it is labelled as a 1 gig chip so it isn't a matter of being shipped the wrong chip. My question is this: Did I get shafted and the manufacturer mislabeled the chip or is it possible that for some reason my computer can't/won't recognize a 1 gig chip?

Any answers or suggestions on what I should do would be greatly appreciated.

 

[Blue Velvet]

Where did you get this RAM from? And did you specify it yourself?

 

[Ogre55]

I got it from oempcworld.com...I know probablly should have stuck to bigger dealer but it was significantly cheaper. I don't know what you mean by specify it. It's specs matched those that apple said I needed, if that is what you mean.

 

[CanadaRAM]

What happened is you got a RAM module with the wrong configuration of chips -- your Mac is only reading half the capacity of the module.
Send those back, they are not compatible and should have never been sold to you for a iBook.

Advice: The "spec" of PC2700 or PC2100 SODIMM CL2.5 is NOT sufficient to determine compatibility. I advise that you buy only from a dealer who tests and guarantees compatibility with your specific model of Mac. Buying incompatible RAM wastes everything saved on the costs of shipping and possibly restocking fees.

 

[ct77]

Ogre55: Check out Ramjet .

Much recommended...

 

[Ogre55]

Thanks for the help. On the RAMjet sight. The memory they offer for the ibook is PC2700. Since it comes with a PC2100 chip soddered to the motherboard, am I just wasting money buying a faster chip? Someone told me that all RAM runs at the speed of the slowest chip. Is this true?

 

[ct77]

Thanks for the help. On the RAMjet sight. The memory they offer for the ibook is PC2700. Since it comes with a PC2100 chip soddered to the motherboard, am I just wasting money buying a faster chip? Someone told me that all RAM runs at the speed of the slowest chip. Is this true?

I'm not certain. You might consider calling Ramjet and asking them.

Of course Ramjet has a potential bias (they'd like to make a sale) but they do build their reputation on being the "honest and helpful RAM seller" so perhaps you could trust them.

Another option might be visiting the Genius Bar and asking your question at an Apple Store, if you have any nearby.

 

[matticus008]

Thanks for the help. On the RAMjet sight. The memory they offer for the ibook is PC2700. Since it comes with a PC2100 chip soddered to the motherboard, am I just wasting money buying a faster chip? Someone told me that all RAM runs at the speed of the slowest chip. Is this true?

The RAM will only run as fast as the bus, or, as you say, the slowest board in the bank. Buying faster RAM (if it is compatible) is a better idea, because you can often use it with newer systems. If you were to switch to a PowerBook in the near future, you could reuse the RAM, whereas if it were PC2100, it wouldn't be wise to do so. Also, if you sell your RAM in the future, the faster it is, the more it's worth. Faster RAM also often has the benefit of lower latency/faster timings, which can improve memory performance even if you're not using the full rated speed.

 

[CanadaRAM]

Faster RAM also often has the benefit of lower latency/faster timings, which can improve memory performance even if you're not using the full rated speed.

Not really. Apple says that lower latency does not make a difference. I have not yet seen any evidence that Apple motherboards have the ability to adjust to faster latency timings.

And in general, the "faster" the RAM gets (in rated MHz), the worse the latency gets. CL 2.5 is common in PC2700 1 Gb DIMMs, but most 1 Gb PC3200 DIMMs are CL3.0. Getting CL 2.5 or 2.0 in DIMMs faster than PC3200 gets hella expensive.

Granted, many PC3200 DIMMs at CL3.0 will run CL2.5 if clocked down to PC2700.

PS: Also compare Data Memory Systems http://www.datamem.com along with RAMJet.

 

[matticus008]

Not really. Apple says that lower latency does not make a difference. I have not yet seen any evidence that Apple motherboards have the ability to adjust to faster latency timings.

Huh. That's good to know. I suppose without any sort of BIOS to set these things, there's no way to change the memory timings, so the lower latency capabilities wouldn't matter since you couldn't select them anyway.