found this:
Problem: Setup forces computer to reboot, and never finishes installation
What to try:
Sometimes setup fails when recovery partitions are still present. For example, Acer and HP both put a special recovery partition on their systems, that cannot be easily deleted.
To delete the partition using Diskpart:
Open a copy of Diskpart following the instructions given earlier.
Enter
list disk
Enter
select disk n
Enter
list partition
Enter
select partition n
Enter
delete partition override
Now try reinstalling Windows.
This is here:
Common Installation Problems and Their Solutions