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Beamtracer
05-25-2003, 09:11 PM
There's a lot of bad RAM out there. RAM that is not up to the quality that is required in Mac OS X.

I've recently had a problem with one of my G4 machines that turned out to be caused by bad RAM. Applications quitting. Lots of kernel panics. Apple's Hardware Test CD didn't reveal anything. (TIP: Holding down Control+L makes the hardware test go into Loop mode if you want to run it overnight)

Taking the 3rd party RAM out and replacing it with Apple supplied RAM solved the problem.

Of course, Apple doesn't manufacture RAM. Most RAM is made in Korea. Currently Apple has been sourcing its RAM from Samsung, but this changes from time to time.

The big five RAM manufacturers are:
[list=1]
Samsung
.
Hynix
.
Micron
.
Infineon
.
Nanya
[/list=1]
Some of the other RAM manufacturers not on this list offer very shonky RAM.

The difference with Apple RAM is that Apple has a tighter level of quality control which your local Apple retailer may not. Apple's RAM also complies to the 'JEDEC' specification. I'm beginning to think that it may always be worth paying the extra money to buy RAM straight from Apple, rather than using 3rd party stuff.

Another advantage with Apple RAM is that it forces them to take responsibility for your whole machine if something goes wrong. That is, while under warranty, Apple must diagnose and solve any problems your computer has, at their expense.

If you are using 3rd party RAM and something goes wrong, it's a different situation. If your local Apple service center spends time finding out what the fault is, then it turns out to be 3rd party RAM, they'll charge you for the cost of this diagnosis.

As computers get faster and use more RAM, problems with RAM will increase exponentially. OS X seems to be much more sensitive to RAM than OS 9 was, and there are many cases of people upgrading to OS X and then experiencing instability, which turns out to be the RAM. Also, as RAM cards get bigger and the circuitry smaller, they are more prone to electrstatic discharge.

If installing RAM, always touch some metal objects or the inside chasis of your machine before installing the RAM. This discharges any static electricity, which may damage your RAM. Some people prefer to wear a Static Strap, which is a curly cable which goes between your hand and a nearby metal object to take the charge away.

After installing RAM or PCI boards it can sometimes help to reset the logic board. This is done by hitting the PMU reset button (formerly known as the CUDA switch). Before you try this, do a search on Apple's support pages for proper instructions and precautions.

claw
05-26-2003, 06:05 AM
So you had the same problem that I did:)

I was ready to throw this G4 thru my windows before I found the bad ram-module. Seems like OSX is more sensitive on bad ram than OS9 was.

toby
05-26-2003, 02:18 PM
yea, in the service dept. where I used to work the technicians found the same thing on several occasions - ram worked fine in OS9 but not X

Johnny
05-26-2003, 06:21 PM
Yeah..I'm thinking that's the way to go...buying the RAM straight from Apple..

there's nothing like that whoa, sh*t feeling you get when it seems your machine is going over the falls with RAM issues.

Any idea on how much 2GB of RAM, bought thru Apple, will cost?

J

aloysius1001
05-26-2003, 07:40 PM
I have 1.25GB in my G4 one Gig of which is from PNY and it seems to work fine and is way cheaper than buying it from Apple.

Beamtracer
05-26-2003, 09:50 PM
In many cases 3rd party RAM may work fine. However if it does fail in its first year you'll have to pay your Apple Service Center if you want them to find the problem.

When RAM fails, there are 'hard failures' and 'soft failures'. A hard failure is easier to diagnose, as your machine probably won't boot up. In a soft failure, you might occasionally have an application disappear, or the OS might suddenly revert back to the log-in screen.

If you are getting soft failures and then take your machine (under warranty) back to the Apple service center, your machine may not repeat the fault in front of them. They may tell you there's nothing wrong with your machine. They don't have time to test it for hours. They may also charge you a fee for telling you that there's nothing wrong with your machine.

Sometims RAM may work OK for the first few months. Then, after soft failures begin, they can grow worse over time. The problems start to compound, and can even cause corruption on the hard drive.

Anyone getting these type of problems should read the forum over on the MacInTouch website, where hundreds of people are reporting RAM related problems...
http://www.macintouch.com/badram01.html

I've learned that there is Apple RAM and Apple RAM. Apple sells a lower grade RAM to resellers than it sells directly to customers. The stuff that Apple sells directly on the Apple Store (on the web) has been quality tested, while the RAM they sell to the local reseller hasn't been tested, even though both are branded as Apple RAM. Within Apple, they refer to the tested RAM as "factory RAM."

Johnny
05-26-2003, 11:20 PM
Originally posted by Beamtracer
Apple sells a lower grade RAM to resellers than it sells directly to customers. The stuff that Apple sells directly on the Apple Store (on the web) has been quality tested, while the RAM they sell to the local reseller hasn't been tested, even though both are branded as Apple RAM. Within Apple, they refer to the tested RAM as "factory RAM."

So, without naming names, you mean by 'reseller' catalog companies and physical stores that sell Macs, right?

J

Beamtracer
05-26-2003, 11:26 PM
Yeah, the stores that sell Macs but aren't owned by Apple. They've been selling Apple branded RAM that has not been tested as thoroughly as the RAM you can buy off Apple's own website.

'Soft' RAM failures can be one of the most insidious faults that can plague your computer. That's why I advise everyone to make a careful decision when they purchase RAM.