Have you checked the board for any blown caps? With such an error its hard to pin down the cause but here is the things I have done to pin down such a problem...1.- Download "Hiren's Boot CD" on a good system and burn it. When you boot off the Hiren's CD run the CPU and memory tests, this will let you know if the CPU or RAM is fried. 2.- The next part you should look at is the power supply...is it getting really hot? is there any burnt smell?
3.- The last one you probably won't like but short of just going on Craigslist and replacing the machine (which wouldn't be a bad idea, considering the age) will probably be your cheapest bet, replace the motherboard. Due to the age of your system it would probably be better to get a new AMD APU...