one would need some sort of magnifier and a trained eye for such. I don't think anyone here, from just your description of the event, is going to know if damage has occurred or not. Damage to a component by a user is never covered by warranty so it would be up to you to negotiate this with the seller. You'll still need to remove the thermal pad. Mineral spirits will usually soften it enough to remove the residue. Goo Gone is basically such.
I just built a new PC but the motherboard did no work and I had to send it back. When I tried to remove the heatsink I found that the thermal pad that it came with had stuck to the CPU. I accidentally pulled the CPU out of the socket without releasing it. Do you think my CPU has been damaged? If so will the AMD warranty cover it? I was using their heatsink and thermal pad.

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