Ok. Well some of you arent quite sure what you are talking about.
Before you tell him to get quad core processors and new power supplies and upgrade his video card, did anyone even look up the chipset specs? Or perhaps, does anyone have little pang of intuition that says "maybe a P4 chipset wont work with a fancy C2D chip"
Well it wont. Here you go read up.
http://www.intel.com/products/chipsets/925X/index.htm
The bus speed of P4's is a 800mhz. Since C2D came out, we have reached 1066, and more recently 1333 (and 1600 on server parts and stuff).
800 started being phased out before the P4 was even discontinued. The 4xxx series C2D chips (ie. obsolete allendale cores with only 2mb of cache) had an 800mhz bus, but Im still not sure about compatibility with your board, as the Intel website never mentions using core chips in it.
You need a new motherboard, pay careful attention to what chipset you get. try and get like the newest or second newest one. I think P35 is cool? Anyways my personal processor recommendation is the 6750, as is the cheapest 1333mhz bus chip I can find around my area at least ($200). But pick up a wollfdale if you can find one

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These charts might help you. They helped me
http://www.techarp.com/showarticle.aspx?artno=337
Also Intel hasnt changed its socket in like 4 years. Amd keeps changing its socket

. And you dont need a new power supply, the power on your chip is around 90W, all the 65nm ones are 65W (except mobile etc). Use the charts
