Shut-off after 60 seconds Bitlocker

Have you tried booting in safe mode? www.vindamedia.com/windows/help/how-to-boot-in-safe-mode

I have exactly the same problem with a Dell XPS8700. It will frequently take at least 2 or 3 attempts to get the password in before it closes down. The most it has ever gone is about 6 times before it would accept the whole password (17 characters). I have never seen it stay on for more than 10 seconds at anytime. I have had the problem ever since I activated Bitlocker. I would really like to know what the issue is, I'm stumped.

Thanks very much for this suggestion! I had also done a few Google searches, strange enough I had not come across this link. I'm going to ask Gigabyte, the manufacturer of my motherboard, about this.

I've checked around, and there are a few people experiencing this problem. The change log for BIOS updates on some systems implies that this might be fixed by a BIOS update: see, e.g., http://ebookily.net/txt/wwwfujitsucom-136652684.html.

Still haven't found a solution, but I'm pretty sure my power supply and the hdd are OK, there is no overheating, and disabling BIOS power saving options also didn't affect it. I swapped the psu and hdd (with different models) to see if they are the culprit.