"....I doubt that you could do this for large amounts of kit, though." Ermm.... <cough>maybe<cough>. Strange things, PCs, you just never know how unreliable they can become once that warranty has expired and the new ones have arrived. It's not like we'd falsify records to make it look like they'd been dropping like flies in their third year of use, no sir! And of course, if you have already agreed with the beancounters that after a certain point in the lifecycle, it is uneconomic to investigate a "non-booting" machine and that a "non-booting PC" = "broken", i.e., an asset write-off, then you are left with a pile of "broken" PCs to dispose of. Of course, we do have USB keys with disk-wiping tools for data-wiping servers, and they might reproduce exactly the same "non-booting" symptoms should they by chance be used on a PC, but I'm fairly sure that never happens.
Should a member of staff then ask if they can remove a "broken" PC as spares we have a form that includes statements around them ensuring it is disposed of in a WEEE-compliant manner, etc. Strangely enough, staff seem to find it very easy to "fix" these broken PCs (could be something to do with the factory CD packs we also dispose of which each PC). Less of a headache for the beancounters, and lots of "broken" PCs going to local charities and staff homes. Just needs a bit of planning an collaboration with the beancounters. Alledgedly. As long as you ignore the M$ licensing issues. <Cough, cough>.