Currently my organization has about 400 PCs. This PC have to be updated for its BIOS files, motherboard drivers, BUS drivers, Windows ( 98 and above) and the virus pattern. Since we only have 2 of technician, this task has put us on so much burden.
An organization of that size should not only have more than two techs, but have already centralized all user systems into logging into a domain and using Active Directory or otherwise to manage resources. If the machines are in fairly similar groups, it wouldn't be that hard to push down a logon script which performs most of the updates automatically. But that's assuming you're using a domain model.
Please tell me that your org uses a domain model... :/