There are some free tools out there than can view the SMBios. Sometimes the data is there, sometimes it is not. However, usually there is some data, so I would guess the problem is not that the BIOS is missing data, though I couldn't rule it out without checking.
LANDesk now uses WMI to view the SMBios.
So if WMI is broken on those machines, that may be the reason you are not getting BIOS data.
Search this community and Google for info on fixing or repairing the SMBios.
That seemed to be the problem. If WMI is corrupt there is a script to run in a batch file at Inventory scan on clients is failing to run. After running this in a batch file I did a full inventory scan and my workstations are now reporting all info. Thanks for the help.
Glad that fixed it. I had an hunch that fixing WMI was the correct answer.