if i were you, i'll go switch the PSU to a better one, say a nice, strong single +12 rail

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ok, anyway... usually, when i overclock, i'll find the highest my CPU can go with stock memory clock, in order to do that, you have to use memory divider, limiting your memory clock to DDR400 (200MHz x 2) or below to ensure, the RAM clock woudn't be too high), from there, increase your CPU FSB by 5MHz or 10MHz until you can't log on to windows, until then... just keep increasing

, say at 250MHz x 9 (your CPU's multiplier is @ 9.0x), the system locked up, don't be afraid, reboot (hard-reboot if you have to) and decrease to say... 240MHz and reboot... should be ok to log on to windows, kindly run a short test, in this "section", i prefer use SuperPI 1M calculation, quick and simple, if your system shows an error in 1M calculation meaning your system's not stable, either play with vCORE or decreasing the CPU FSB until you managed to get passed in 1M SuperPI calculation... say, you passed on 235MHz @SuperPI 1M calculation, it's time for your system running on long run test, 32M SuperPI should be ok, but i prefer Prime95, run it overnight >5Hrs considered stable enough (for me la...)
same goes to memory, finding highest memory clock... set the CPU multiplier down to 5x, with stock memory clock (not using the memory divider), slightly increase the CPU FSB until you managed to find a good stable memory clock...

, testing and testing all same as CPU test (above)...
recommend me the minimum power supply that i can use..