Kurt replaced the hard drive in his Lenovo laptop and now it won't boot up. It stops at the boot screen. 24 hours later, it booted up no problem. What gives? Leo says that's common and usually results in a hiccup in the BIOS or UEFI. Leo suspects that the battery on the motherboard has failed. Also, underneath the splash screen could show if the computer tried to boot into Windows and failed. That could indicate a faulty hard drive. Leo suspects a failing power supply could also be the issue.