i am using athlon 2000XP.the clock ratio is 133*12.5 and memory is 512mb kingston pc133 sdram.the default vcore voltage is 1.72v.when i try to increase the fsb to 140 and run prime95,but a eeror come out.is my vcore too low?last time i am using t-birds 1.33ghz and i am able to raise the fsb to 140 without any problem.can i know what is the problem and what the vcore voltage is the best?