My dad was getting ansy to get a new PC so he decided we should buy the parts and build it ourselves. So our journey commensed. I went with my mom to Fry's to get the motherboard, memory, cpu and hard drive. I choose a P4 2.4Ghz for the cpu and a ECS motherboard and 256 megs of memory.
The total was $112 dollars for the cpu and motherboard because they were on sale on $90.00 for the memory because it was not on sale addionally I got a western digital 160GB hard drive for $60.00. We got home and plug eveything together and found out that the power supply that was in the box we already had wouldn't work with the new motherboard. It turns out that the P4 draws so much power that they had to add another power connector to the motherboard. After we got a new power supply for $15 dollars it was smooth sailing.
So there it how to get a new computer for under $300 dollars assuming you already have all those pesky peripherals.