I sent my T410S to a small shop for fan replacement. They told me they would replace the defective one with a brand new one.
I have got it back from the shop but I want to check to make sure that the fan is indeed replaced with a new fan rather than the current one.
Without disassembling the laptop, how can I check that the fan is a new/different one from the previous that comes with the laptop when I bought it?
There is no real easy way of checking whether the fan is replaced or not, since there is no unique serial number, and doesn't report itself with any unique identifier to the system.
With minor dissasembly, you can take the keyboard off and check to see if the fan vane has any dusts on it or not. An old fan will have some dust particles stuck to the surface even when they are cleaned, but a new one will have a waxy clean vane surface.