Help with overclocking fx 4100

currently at 3.6 ghz at 1.35 vcore. i was running it at 4ghz at the same stock vcore which is 1.35. it was stable with prime 95. im thinking about overclocking it back up to 4ghz, i tried 4.4 ghz and bumped the vcore up to 1.375 but it wasnt stable. first does anyone think that i should bump up the vcore past 1.35 for 4ghz? secondly any help with oc to 4.4 ghz would be appreciated. im not overclocking any ram so i dont think i need to touch the northbdge frequencies or voltages. can someone help

each chip will be different voltage and result high clock , so you try it yourself by raising the vCore and test again