I doubt I have the answer to your question.
Is the memory new, is it all on one stick?
Is the memory over heating?
I once had a similar problem installing 512mb of ram with win98 but worked fine with 256mb of ram.
I was once told that win98 does not handle large amounts of ram as it was designed when 128mb of ram was considered alot.
I do not know if this is really true. I hope somebody else will have a better answer than mine.
Good Luck.....
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