[Ti] G4/400 Freezing Constantly: MORE

[Kynan Shook]

Tristan Cunningham <triscunn at gmail.com> writes:
> I ran MemtestOSX on the 256MB module and it reported no problems --  
> how
> accurate is this check (hopefully more so than the Disk Check  
> utility that
> comes with OS X?)? Is it safe to assume that memory is not the  
> culprit if
> this program does not find issues with it?


No.  I'd give any software memory test maybe a 5% chance at best of  
detecting bad RAM.  The kind of defects that a software test can find  
are so obvious that the manufacturer never should have shipped the  
RAM in the first place.  The Apple Authorized Service Provider I used  
to work for invested about $5,000 in a small hardware box designed  
solely for the purpose of testing memory, and even that only had  
maybe a 75% chance of catching bad RAM.  There are so many variables  
involved that the only real way to test for it with good certainty is  
to remove the stick of RAM and see if bad things stop happening.  In  
your case, I'd recommend also reformatting (or bare minimum, running  
DiskWarrior after pulling the RAM), because I wouldn't be surprised  
if your directory is corrupted too.

One of the other good "tests" I have: who manufactured the chips on  
the memory module, and who manufactured the module?  If the chips are  
not labeled with a manufacturer or they are covered somehow, don't  
trust the memory.  There are also a wide variety of module and chip  
manufacturers that I wouldn't trust, even if they do label their  
product.  The best quality out there is Samsung.  I think I'd  
probably give #2 to Micron, often sold under the Crucial brand name,  
but only if they actually use Micron chips (labeled with an MT logo  
somewhere).