Why not use Dell's fresh install and see if that fixes it?
I started to have Windows Vista boot problems after I cloned the old HDD to the new HDD and used the new HDD as the boot HDD. It is a Dell Dimension E521 desktop computer and the boot problems are as follows.
The computer can boot every other time. When it runs into boot problems, it stops at loading the BIOS. I cannot press F2 nor F12 to enter the BIOS menu either. But if I press the reset button to force it to stop and press it again to start, it will work just fine.
Can someone give me pointers on how to debug? Thanks.
David

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