i met the same thing once

i exchaged every component(harddriver, memory, cpu, motherboard ...) i suspected. finally i found out the cpu has problem.

this cpu is weird, it can boot-up, pass post, and begin to install system. but same as u said it just suddenly crashed in the middle of installation. and each time it happened randomly during this process. then i chaged an another healthy cpu, the installation was so smooth.

good thing for this cpu is that it still can be used in a normal working system(just replace the healthy cpu with this defective one), but it will automatically reboot the system in anytime when u are using it. how long will it keep the normally working status? well, it depends on your luck.