I have a Dell Inspiron 1720 (circa 2007).  It is currently running Windows 7 and Ubuntu 11.10.  I have upgraded the BIOS to A09.  I had a hard drive failure and had to reinstall everything.  Now, when I start up, the Bios will load quickly (from a previous shut down)  but it will hang, and then say, "drive not detected".

When I restart the computer by holding the power button, the BIOS starts, and I press F12 to get to the boot menu so that I can select Internal HDD.  This is the only way that I can get my computer to boot up properly after a sleep mode or a power down, or anything like that.

Any ideas?