Over-clock FAIL

[realbaz]

After purchasing a new powerpack, i overclocked my FSB to 250, lowerd my ram from 1066 to 833 mhz (couldnt find ram multiplier) the computer loaded into the desktop, then crashed. any ideas?

i am running

INTEL PENTIUM DUAL CORE E5200 RUNNING @ 2.50GHz
Biostar P43-a7
4gb DDR2 ram
Nvidia 8400 GS
Psu : 600 W,

 

[realbaz]

I purchased it from a shop in my local town , tested it and it output around 580W, anyway why could my pc be freezing? i will consider getting a better psu

 

[realbaz]

thanks & its Done, and i increased the voltage by 5%

 

[realbaz]

I didnt do the testing, one of the hardware specialists from collage did, it seems to boot up stable with around 240 FSB, but the pc hangs on stress tests, would it be best to increase voltage or decrease FSB? && im getting a better psu within the next month or two.