setfsb overclocking reduced after adding ram

gamepoint

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Feb 25, 2013
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i first had 2gb ddr2 ram 800mhz and with set fsb i was able to overclock my cpu from 2.8ghz to 3.245 ghz but after adding another 2gb ram 667mhz, i am only able to go high as 3.105 ghz. anything higher freezes system but before my system only started to freeze after 3.245 ghz

sys: c2d e7400 2.8ghz
4 gb ram ddr2
zotac gtx 650 1gb
corsair vs450
 

gamepoint

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Feb 25, 2013
72
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10,630

is there any way, i can oc above 3.1 ghz without freezeing as after oc my cpu only gets hot as maximum as 53c(while playing big games like crysis 3, battlefield 4) and at desktop it remain at 38c.

My cpu can handle as maximum as 73c.