This is a common problem and I have run into it more than enough times.
First thing to do is make sure your memory is working fine by running memtest for a few hours.
If memory turns out to not be the problem, go into your BIOS and disable all components that are not neccesary and remove all unneccesary periphiral cards (eg modems, sound cards, onboard LAN etc.) and try again. If this works, go back into the BIOS and turn them back on one by one and make sure the system boots. If it doesn't, one of your components probably has an IRQ conflict
If you successfully are able to install Windows, I suggest you install the HAL (Hardware abstraction layer) which allows you to manually assign IRQs and avoid conflicts