I suggest you talk to the hardware gays and gals on the hardware boards - this is not my speciallity.
But yes format, install sould work, unless the drives were fried in a spike.

Haven't done a reinstall yet. When I boot up I get the error message "no boot sector on hard drive". I have two Dell servers that this has happened to from the time I went to bed last night until I got up this morning. Have tested hard drive utilities provided by Dell support and no errors on hard drive. Seems to be at controller level. Could a virus do this? May be a power spike? If I format HD with System utiltiy will this allow me to reinstall OS?

Thanks for your reply

By the sounds of it - you are into a reinstall after the format of the drive. It may have been a drive fail rather than a virus.