I had this problem in the past
Wich operating system do you have ?
windows 2000 and XP support more than 192megs of ram but not windows 95,98, or ME
In windows ME in the past I have 256 megs of ram and when I test it with Norton,
Norton found a default stick ???
In windows 2000 or XP all is ok
I run XP with 512 megs of ram and all is working fine and I run the same stick that cause a fault in windows ME
The question is what is your OS ?