I don't have much experience with Dell servers, but I did buy 13 Sun V240 and V440 servers for $150, and did really well with them.
The Sun servers had 2.5-3 lb motherboards in each, 0.5-1.5 lbs RAM in each, a few lbs of CPU boards in the V440's @ $4.50/lb, 10 lbs of power supplies in each @ 0.30/lb, plus sold all the CPU's on
ebay for $200, plus aluminum, steel, and some copper. I made at least $450 on this lot.
I love to scrap servers, usually much better than PC's. Many of them have very nice copper heat sinks too, up to 2 lbs.
I pay $5 - 25 each for scrap servers, depending on what model and what is inside.
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