but you have not mentioned which iBook your colleague has, or what version of the Mac OS it is running.
If, on removing the RAM, the machine functions normally, I would suspect that the RAM was faulty.
Pass on a little more information and we'll go from there.
BTW, most RAM from reputable companies is warranted for life.
P
My colleague bought a Kingston 512MB Extended Memory to install on his ibook. The ibook detected the memory, and updated the total RAM as 768MB (512 + 256). Everything seems alright, but after working for a very short while, the ibook will stop responding. He restarts the ibook, and after a while, the machine "hang" again. If he removes the 512 memory, the machine will work fine.
Could this be the problem of the RAM? Or what other reasons can there be?

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