A working server with a license is worth a lot more. If there is no licensed server OS it's worth a little less and no drives even less. But drives rarely get full value in the servers so my bet is best prices are drives on their own and the server with a drive so it boots and runs.
Remember drives are dirt cheap so don't expect anywhere near what the purchase price. And Seagates? I give folk a happy meal for each one.
I participated in an office closing and am now the owner of several large operational servers I wish to sell. I want them to get the most use and get the most buck for my bang. I'm thinking I should include one original hard drive just to get the standard asking price for each model, rather than selling a stack of hard drives separately or loading the servers with extra ones that will not be noticed in the ad. I know there are technical values but I don't know what is attractive to buyers.

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