I already have search other ways of automated compatibility detectors and websites to know it but unable to find cpu that supports both of above.
Update: I have installed core 2 quad q9400 and it is working fine but the shopkeeper said that if the electricity voltage varies too much then the processor may corrupt the bios. My cabinet AC voltage capacity is 230V. is it fine for the q9400 processor?
most of the better power supplies can handle either 230v or 120v automatically, It is your power supply that converts the 240/120 to the d/c lower voltages that your pc needs. If you incoming 230 or 120 volts are subject to wide variances of more that 10% then you should have a UPS (Uninterruptible Power Supply) to "clean" the power from the wall to your power supply in your pc and provide protection if you should lose power from your electric utility provider.
haha yep when you have some doubt before make something consider ask to someone here, I'm sure that some member help you fastly good luck with your rig dude