dell studio 1555 7 beep code

会员135031

hello,
i have a dell studio 1555 all power planes ok 3.3v,5v,1.5v,1.06v,1.8v all okay
i have changed all the  micom 8712e ,82801ibm,ati 216-0728018
when i power on it come on 7 beeps no display and shuts off after 15secs
i noticed cpu fan does not come on the cpu and graphic get hot.
7 beep code mean cpu cache error where can be the problem pls help.

会员751262

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