My system bios screen comes up (DELL) and then freezes for a minute then a message appears can't find primary drive.
hit F2 for set or F! to continue.  I have done the setup and double checked everything appears OK, If I hit F! it boots up
What is wrong?

First, check the Dell support web site for this problem for your computer.

My suggestions:
Several other possibilities exist, if there is no error in the BIOS setup.
1) The wrong partition on your hard drive may be marked as active. You can check this in the control panel under administrative tools\computer management\storage\disk management.
2)Master boot record may be corrupted. You can use the recovery console command fixmbr to correct this problem.
3)Hard drive may have hardware problems. If you know the manufacturer of the hard drive, you can get a diagnostic program on their web site to check the drive for problems.