My pc Crash while playing wow

My pc is crashing while im playing wow. 2 day ago i changed my MB and Cpu. For sure i format and reinstall everyting.
here is my info of my PC:

CPu Duo core Intel 3.00Ghz
MB P5Q SE
DDR2 3ghz (1+1+.512+.512)
Video card X800 pro 512mb
Power supply: 300w

Window XP, (i can't update it from Window update)

When im playing wow my pc reboot but nothing appear on my screen , my button power who is usualy blue become orange, When i press my button reset it doesnt reset instantly its event pretty hard to restart normally, i need to hold my Start button 5-8sec to close it and press it again to restart.

Anyone can help me with this?
Thx a lot
PS : sorry for my english its not my first language

Do you have all the drivers? Like importantly graphics card drivers. Also get a 400 or 450 Watt Power Supply. Might help you. :thumbup1:

Basically the 300w power supply is minimum recommendation for the system. You are running a high end graphic game. Your system configuration looks enough capable to compile with it. The problem can be either in the power supply for the sound / music drivers. Try to play the game while keeping the sound off. If nothing happens then there is definitely a sound driver mess. Update it. After just check out for the power supply . If you use 400 to 500w PSU of good quality then things can work much better. Second thing there must be a error log in c:\programs files\world of worcraft\errors. Look at the log file you will get an basic idea about the problem.