fedora10 is hanging when using memory greater than 1 GB

[balu mohan]

hi..i am using fedora10..my pc config is(intel 915series borad,1.5gb
ram(1gb+512),256 Nvidia grafics card)

my problem is,wen i am using this 1.5 gb ram i cant use fedoara...after
entering the username and password the pc become hang....i cant do anything

but wen itried to boot after removing the 512 ram..its booting...both ram
havin the same processing speed..
i tried with adding 1 more 512 ram...but then also the same problem and i
done memory test also...it also shows tat there is no errors with my memory.

what should i do?????

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With Regards
AgEnT fRoM ThE hEaVeN
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