I have had many issues with this comupter, but my Dell Inspirton 1545 had started to read "no bootable devices" and wouldn't start at all. Now, after buying and installing a brand new harddrive, it reads it again, but only SOMETIMES! When it gives me options of rebooting or running a diagnostics test, if I switch some stuff around or restart it, or even just leave it alone for a little while, I can start it and it works fine. Except after a short while of using it, it will malfunction and go to "no bootable devices" page again. Tech support says that the hard drive may not be connected properly, but I don't know what to do!