Joaquito, Thank you very much for joining the Intel® Desktop Boards communities and for sharing those details.
To answer your question, yes, your speculations are true, the board is capable to support up to 8GB of memory RAM, which means the max size of memory RAM for each DIMM slot is 2GB, as you can confirm on the following links:
Any further questions, please let me know.
Just some more info to help you decode your RAM:
Kingston sells 'kits' and the trailing number is the sum of the total RAM in the kit. Does the part number have 'K2/4G', or just '/4G' on the end of it?
This should help you further: https://www.kingston.com/en/memory/valueram/valueram_decoder
Joaquito, You are welcome.
Thank very much for letting us know that information. And yes, in this case that will be the best option to try, hopefully you will be able to sell it or find a store to trade it.
Any other inquiry, do not hesitate in contact us again.